diff --git a/.github/workflows/discord_notify.yml b/.github/workflows/discord_notify.yml index ff2caa1bf..c8db43932 100644 --- a/.github/workflows/discord_notify.yml +++ b/.github/workflows/discord_notify.yml @@ -2,11 +2,26 @@ name: Discord Notify on: pull_request_target: +<<<<<<< HEAD types: [ labeled ] jobs: notify: if: ${{ github.event.label.name == 'React Core Team' }} +======= + types: [opened, ready_for_review] + +jobs: + check_maintainer: + uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main + with: + actor: ${{ github.event.pull_request.user.login }} + is_remote: true + + notify: + if: ${{ needs.check_maintainer.outputs.is_core_team == 'true' }} + needs: check_maintainer +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff runs-on: ubuntu-latest steps: - name: Discord Webhook Action @@ -18,4 +33,8 @@ jobs: embed-author-icon-url: ${{ github.event.pull_request.user.avatar_url }} embed-title: '#${{ github.event.number }} (+${{github.event.pull_request.additions}} -${{github.event.pull_request.deletions}}): ${{ github.event.pull_request.title }}' embed-description: ${{ github.event.pull_request.body }} - embed-url: ${{ github.event.pull_request.html_url }} \ No newline at end of file +<<<<<<< HEAD + embed-url: ${{ github.event.pull_request.html_url }} +======= + embed-url: ${{ github.event.pull_request.html_url }} +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff diff --git a/.github/workflows/label_core_team_prs.yml b/.github/workflows/label_core_team_prs.yml new file mode 100644 index 000000000..3d9fa2be1 --- /dev/null +++ b/.github/workflows/label_core_team_prs.yml @@ -0,0 +1,32 @@ +name: Label Core Team PRs + +on: + pull_request_target: + +env: + TZ: /usr/share/zoneinfo/America/Los_Angeles + # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout + SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1 + +jobs: + check_maintainer: + uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main + with: + actor: ${{ github.event.pull_request.user.login }} + is_remote: true + + label: + if: ${{ needs.check_maintainer.outputs.is_core_team == 'true' }} + runs-on: ubuntu-latest + needs: check_maintainer + steps: + - name: Label PR as React Core Team + uses: actions/github-script@v7 + with: + script: | + github.rest.issues.addLabels({ + owner: context.repo.owner, + repo: context.repo.repo, + issue_number: ${{ github.event.number }}, + labels: ['React Core Team'] + }); diff --git a/next-env.d.ts b/next-env.d.ts index 52e831b43..8af49a0d7 100644 --- a/next-env.d.ts +++ b/next-env.d.ts @@ -1,5 +1,10 @@ /// /// +/// // NOTE: This file should not be edited +<<<<<<< HEAD // see https://nextjs.org/docs/pages/api-reference/config/typescript for more information. +======= +// see https://nextjs.org/docs/app/api-reference/config/typescript for more information. +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff diff --git a/package.json b/package.json index 07e6136e6..6d6b53f92 100644 --- a/package.json +++ b/package.json @@ -24,8 +24,8 @@ }, "dependencies": { "@codesandbox/sandpack-react": "2.13.5", - "@docsearch/css": "^3.6.1", - "@docsearch/react": "^3.6.1", + "@docsearch/css": "^3.8.3", + "@docsearch/react": "^3.8.3", "@headlessui/react": "^1.7.0", "@radix-ui/react-context-menu": "^2.1.5", "body-scroll-lock": "^3.1.3", diff --git a/public/images/team/andrey-lunyov.jpg b/public/images/team/andrey-lunyov.jpg deleted file mode 100644 index aeaaec06a..000000000 Binary files a/public/images/team/andrey-lunyov.jpg and /dev/null differ diff --git a/public/images/team/hendrik.jpg b/public/images/team/hendrik.jpg new file mode 100644 index 000000000..b39ea5be2 Binary files /dev/null and b/public/images/team/hendrik.jpg differ diff --git a/public/images/team/jordan.jpg b/public/images/team/jordan.jpg new file mode 100644 index 000000000..d8874a29f Binary files /dev/null and b/public/images/team/jordan.jpg differ diff --git a/public/images/team/kathryn-middleton.jpg b/public/images/team/kathryn-middleton.jpg deleted file mode 100644 index 904c3b134..000000000 Binary files a/public/images/team/kathryn-middleton.jpg and /dev/null differ diff --git a/public/images/team/lauren.jpg b/public/images/team/lauren.jpg index 26d46bd2f..a8615aa00 100644 Binary files a/public/images/team/lauren.jpg and b/public/images/team/lauren.jpg differ diff --git a/public/images/team/luna-wei.jpg b/public/images/team/luna-wei.jpg deleted file mode 100644 index cdc4a2b6a..000000000 Binary files a/public/images/team/luna-wei.jpg and /dev/null differ diff --git a/public/images/team/mike.jpg b/public/images/team/mike.jpg new file mode 100644 index 000000000..39fe23fea Binary files /dev/null and b/public/images/team/mike.jpg differ diff --git a/public/images/team/noahlemen.jpg b/public/images/team/noahlemen.jpg deleted file mode 100644 index e3f788d89..000000000 Binary files a/public/images/team/noahlemen.jpg and /dev/null differ diff --git a/public/images/team/pieter.jpg b/public/images/team/pieter.jpg new file mode 100644 index 000000000..d098e5abe Binary files /dev/null and b/public/images/team/pieter.jpg differ diff --git a/public/images/team/sam.jpg b/public/images/team/sam.jpg deleted file mode 100644 index f73474b91..000000000 Binary files a/public/images/team/sam.jpg and /dev/null differ diff --git a/public/images/team/sathya.jpg b/public/images/team/sathya.jpg deleted file mode 100644 index 0f087f4a3..000000000 Binary files a/public/images/team/sathya.jpg and /dev/null differ diff --git a/public/images/team/tianyu.jpg b/public/images/team/tianyu.jpg deleted file mode 100644 index aeb6ed9fa..000000000 Binary files a/public/images/team/tianyu.jpg and /dev/null differ diff --git a/src/components/MDX/CodeBlock/CodeBlock.tsx b/src/components/MDX/CodeBlock/CodeBlock.tsx index 1fd9a8a90..42165c57d 100644 --- a/src/components/MDX/CodeBlock/CodeBlock.tsx +++ b/src/components/MDX/CodeBlock/CodeBlock.tsx @@ -336,6 +336,7 @@ function getInlineDecorators( line.step === 3, 'bg-green-40 border-green-40 text-green-60 dark:text-green-30': line.step === 4, + // TODO: Some codeblocks use up to 6 steps. } ), }) diff --git a/src/components/MDX/TeamMember.tsx b/src/components/MDX/TeamMember.tsx index a49aa728e..2c2fffa73 100644 --- a/src/components/MDX/TeamMember.tsx +++ b/src/components/MDX/TeamMember.tsx @@ -3,7 +3,7 @@ */ import * as React from 'react'; -import Image from 'next/image'; +import Image from 'next/legacy/image'; import {IconTwitter} from '../Icon/IconTwitter'; import {IconThreads} from '../Icon/IconThreads'; import {IconBsky} from '../Icon/IconBsky'; diff --git a/src/content/blog/2022/06/15/react-labs-what-we-have-been-working-on-june-2022.md b/src/content/blog/2022/06/15/react-labs-what-we-have-been-working-on-june-2022.md index 80fcb78e6..1aaa94ec1 100644 --- a/src/content/blog/2022/06/15/react-labs-what-we-have-been-working-on-june-2022.md +++ b/src/content/blog/2022/06/15/react-labs-what-we-have-been-working-on-june-2022.md @@ -27,7 +27,7 @@ We announced an [experimental demo of React Server Components](https://legacy.re In particular, we’re abandoning the idea of having forked I/O libraries (eg react-fetch), and instead adopting an async/await model for better compatibility. This doesn’t technically block RSC’s release because you can also use routers for data fetching. Another change is that we’re also moving away from the file extension approach in favor of [annotating boundaries](https://github.com/reactjs/rfcs/pull/189#issuecomment-1116482278). -We’re working together with Vercel and Shopify to unify bundler support for shared semantics in both Webpack and Vite. Before launch, we want to make sure that the semantics of RSCs are the same across the whole React ecosystem. This is the major blocker for reaching stable. +We’re working together with Vercel and Shopify to unify bundler support for shared semantics in both webpack and Vite. Before launch, we want to make sure that the semantics of RSCs are the same across the whole React ecosystem. This is the major blocker for reaching stable. ## Asset Loading {/*asset-loading*/} diff --git a/src/content/blog/2024/04/25/react-19-upgrade-guide.md b/src/content/blog/2024/04/25/react-19-upgrade-guide.md index fbc4e378c..cb83a6176 100644 --- a/src/content/blog/2024/04/25/react-19-upgrade-guide.md +++ b/src/content/blog/2024/04/25/react-19-upgrade-guide.md @@ -24,7 +24,7 @@ To help make the upgrade to React 19 easier, we've published a `react@18.3` rele We recommend upgrading to React 18.3 first to help identify any issues before upgrading to React 19. -For a list of changes in 18.3 see the [Release Notes](https://github.com/facebook/react/blob/main/CHANGELOG.md). +For a list of changes in 18.3 see the [Release Notes](https://github.com/facebook/react/blob/main/CHANGELOG.md#1830-april-25-2024). @@ -113,7 +113,7 @@ This will run the following codemods from `react-codemod`: - [`replace-string-ref`](https://github.com/reactjs/react-codemod?tab=readme-ov-file#replace-string-ref) - [`replace-act-import`](https://github.com/reactjs/react-codemod?tab=readme-ov-file#replace-act-import) - [`replace-use-form-state`](https://github.com/reactjs/react-codemod?tab=readme-ov-file#replace-use-form-state) -- [`prop-types-typescript`](https://codemod.com/registry/react-prop-types-typescript) +- [`prop-types-typescript`](https://github.com/reactjs/react-codemod#react-proptypes-to-prop-types) This does not include the TypeScript changes. See [TypeScript changes](#typescript-changes) below. diff --git a/src/content/blog/2024/12/05/react-19.md b/src/content/blog/2024/12/05/react-19.md index 62a6ce464..aac80a44f 100644 --- a/src/content/blog/2024/12/05/react-19.md +++ b/src/content/blog/2024/12/05/react-19.md @@ -294,7 +294,7 @@ A component was suspended by an uncached promise. Creating promises inside a Cli -To fix, you need to pass a promise from a suspense powered library or framework that supports caching for promises. In the future we plan to ship features to make it easier to cache promises in render. +To fix, you need to pass a promise from a Suspense powered library or framework that supports caching for promises. In the future we plan to ship features to make it easier to cache promises in render. diff --git a/src/content/blog/2025/02/14/sunsetting-create-react-app.md b/src/content/blog/2025/02/14/sunsetting-create-react-app.md new file mode 100644 index 000000000..9ced6231c --- /dev/null +++ b/src/content/blog/2025/02/14/sunsetting-create-react-app.md @@ -0,0 +1,320 @@ +--- +title: "Sunsetting Create React App" +author: Matt Carroll and Ricky Hanlon +date: 2025/02/14 +description: Today, we’re deprecating Create React App for new apps, and encouraging existing apps to migrate to a framework, or to migrate to a build tool like Vite, Parcel, or RSBuild. We’re also providing docs for when a framework isn’t a good fit for your project, you want to build your own framework, or you just want to learn how React works by building a React app from scratch. +--- + +February 14, 2025 by [Matt Carroll](https://twitter.com/mattcarrollcode) and [Ricky Hanlon](https://bsky.app/profile/ricky.fm) + +--- + + + +Today, we’re deprecating [Create React App](https://create-react-app.dev/) for new apps, and encouraging existing apps to migrate to a [framework](#how-to-migrate-to-a-framework), or to [migrate to a build tool](#how-to-migrate-to-a-build-tool) like Vite, Parcel, or RSBuild. + +We’re also providing docs for when a framework isn’t a good fit for your project, you want to build your own framework, or you just want to learn how React works by [building a React app from scratch](/learn/build-a-react-app-from-scratch). + + + +----- + +When we released Create React App in 2016, there was no clear way to build a new React app. + +To create a React app, you had to install a bunch of tools and wire them up together yourself to support basic features like JSX, linting, and hot reloading. This was very tricky to do correctly, so the [community](https://github.com/react-boilerplate/react-boilerplate) [created](https://github.com/kriasoft/react-starter-kit) [boilerplates](https://github.com/petehunt/react-boilerplate) for [common](https://github.com/gaearon/react-hot-boilerplate) [setups](https://github.com/erikras/react-redux-universal-hot-example). However, boilerplates were difficult to update and fragmentation made it difficult for React to release new features. + +Create React App solved these problems by combining several tools into a single recommended configuration. This allowed apps a simple way to upgrade to new tooling features, and allowed the React team to deploy non-trivial tooling changes (Fast Refresh support, React Hooks lint rules) to the broadest possible audience. + +This model became so popular that there's an entire category of tools working this way today. + +## Deprecating Create React App {/*deprecating-create-react-app*/} + +Although Create React App makes it easy to get started, [there are several limitations](#limitations-of-build-tools) that make it difficult to build high performant production apps. In principle, we could solve these problems by essentially evolving it into a [framework](#why-we-recommend-frameworks). + +However, since Create React App currently has no active maintainers, and there are many existing frameworks that solve these problems already, we’ve decided to deprecate Create React App. + +Starting today, if you install a new app, you will see a deprecation warning: + + + + +create-react-app is deprecated. +{'\n\n'} +You can find a list of up-to-date React frameworks on react.dev +For more info see: react.dev/link/cra +{'\n\n'} +This error message will only be shown once per install. + + + + +We've also added a deprecation notice to the Create React App [website](https://create-react-app.dev/) and GitHub [repo](https://github.com/facebook/create-react-app). Create React App will continue working in maintenance mode, and we've published a new version of Create React App to work with React 19. + +## How to Migrate to a Framework {/*how-to-migrate-to-a-framework*/} +We recommend [creating new React apps](/learn/creating-a-react-app) with a framework. All the frameworks we recommend support client-side rendering ([CSR](https://developer.mozilla.org/en-US/docs/Glossary/CSR)) and single-page apps ([SPA](https://developer.mozilla.org/en-US/docs/Glossary/SPA)), and can be deployed to a CDN or static hosting service without a server. + +For existing apps, these guides will help you migrate to a client-only SPA: + +* [Next.js’ Create React App migration guide](https://nextjs.org/docs/app/building-your-application/upgrading/from-create-react-app) +* [React Router’s framework adoption guide](https://reactrouter.com/upgrading/component-routes). +* [Expo webpack to Expo Router migration guide](https://docs.expo.dev/router/migrate/from-expo-webpack/) + +## How to Migrate to a Build Tool {/*how-to-migrate-to-a-build-tool*/} + +If your app has unusual constraints, or you prefer to solve these problems by building your own framework, or you just want to learn how react works from scratch, you can roll your own custom setup with React using Vite, Parcel or Rsbuild. + +For existing apps, these guides will help you migrate to a build tool: + +* [Vite Create React App migration guide](https://www.robinwieruch.de/vite-create-react-app/) +* [Parcel Create React App migration guide](https://parceljs.org/migration/cra/) +* [Rsbuild Create React App migration guide](https://rsbuild.dev/guide/migration/cra) + +To help get started with Vite, Parcel or Rsbuild, we've added new docs for [Building a React App from Scratch](/learn/build-a-react-app-from-scratch). + + + +#### Do I need a framework? {/*do-i-need-a-framework*/} + +Most apps would benefit from a framework, but there are valid cases to build a React app from scratch. A good rule of thumb is if your app needs routing, you would probably benefit from a framework. + +Just like Svelte has Sveltekit, Vue has Nuxt, and Solid has SolidStart, [React recommends using a framework](#why-we-recommend-frameworks) that fully integrates routing into features like data-fetching and code-splitting out of the box. This avoids the pain of needing to write your own complex configurations and essentially build a framework yourself. + +However, you can always [build a React app from scratch](/learn/build-a-react-app-from-scratch) using a build tool like Vite, Parcel, or Rsbuild. + + + +Continue reading to learn more about the [limitations of build tools](#limitations-of-build-tools) and [why we recommend frameworks](#why-we-recommend-frameworks). + +## Limitations of Build Tools {/*limitations-of-build-tools*/} + +Create React App and build tools like it make it easy to get started building a React app. After running `npx create-react-app my-app`, you get a fully configured React app with a development server, linting, and a production build. + +For example, if you're building an internal admin tool, you can start with a landing page: + +```js +export default function App() { + return ( +
+

Welcome to the Admin Tool!

+
+ ) +} +``` + +This allows you to immediately start coding in React with features like JSX, default linting rules, and a bundler to run in both development and production. However, this setup is missing the tools you need to build a real production app. + +Most production apps need solutions to problems like routing, data fetching, and code splitting. + +### Routing {/*routing*/} + +Create React App does not include a specific routing solution. If you're just getting started, one option is to use `useState` to switch between routes. But doing this means that you can't share links to your app - every link would go to the same page - and structuring your app becomes difficult over time: + +```js +import {useState} from 'react'; + +import Home from './Home'; +import Dashboard from './Dashboard'; + +export default function App() { + // ❌ Routing in state does not create URLs + const [route, setRoute] = useState('home'); + return ( +
+ {route === 'home' && } + {route === 'dashboard' && } +
+ ) +} +``` + +This is why most apps that use Create React App solve add routing with a routing library like [React Router](https://reactrouter.com/) or [Tanstack Router](https://tanstack.com/router/latest). With a routing library, you can add additional routes to the app, which provides opinions on the structure of your app, and allows you to start sharing links to routes. For example, with React Router you can define routes: + +```js +import {RouterProvider, createBrowserRouter} from 'react-router'; + +import Home from './Home'; +import Dashboard from './Dashboard'; + +// ✅ Each route has it's own URL +const router = createBrowserRouter([ + {path: '/', element: }, + {path: '/dashboard', element: } +]); + +export default function App() { + return ( + + ) +} +``` + +With this change, you can share a link to `/dashboard` and the app will navigate to the dashboard page . Once you have a routing library, you can add additional features like nested routes, route guards, and route transitions, which are difficult to implement without a routing library. + +There's a tradeoff being made here: the routing library adds complexity to the app, but it also adds features that are difficult to implement without it. + +### Data Fetching {/*data-fetching*/} + +Another common problem in Create React App is data fetching. Create React App does not include a specific data fetching solution. If you're just getting started, a common option is to use `fetch` in an effect to load data. + +But doing this means that the data is fetched after the component renders, which can cause network waterfalls. Network waterfalls are caused by fetching data when your app renders instead of in parallel while the code is downloading: + +```js +export default function Dashboard() { + const [data, setData] = useState(null); + + // ❌ Fetching data in a component causes network waterfalls + useEffect(() => { + fetch('/api/data') + .then(response => response.json()) + .then(data => setData(data)); + }, []); + + return ( +
+ {data.map(item =>
{item.name}
)} +
+ ) +} +``` + +Fetching in an effect means the user has to wait longer to see the content, even though the data could have been fetched earlier. To solve this, you can use a data fetching library like [React Query](https://react-query.tanstack.com/), [SWR](https://swr.vercel.app/), [Apollo](https://www.apollographql.com/docs/react), or [Relay](https://relay.dev/) which provide options to prefetch data so the request is started before the component renders. + +These libraries work best when integrated with your routing "loader" pattern to specify data dependencies at the route level, which allows the router to optimize your data fetches: + +```js +export async function loader() { + const response = await fetch(`/api/data`); + const data = await response.json(); + return data; +} + +// ✅ Fetching data in parallel while the code is downloading +export default function Dashboard({loaderData}) { + return ( +
+ {loaderData.map(item =>
{item.name}
)} +
+ ) +} +``` + +On initial load, the router can fetch the data immediately before the route is rendered. As the user navigates around the app, the router is able to fetch both the data and the route at the same time, parallelizing the fetches. This reduces the time it takes to see the content on the screen, and can improve the user experience. + +However, this requires correctly configuring the loaders in your app and trades off complexity for performance. + +### Code Splitting {/*code-splitting*/} + +Another common problem in Create React App is [code splitting](https://www.patterns.dev/vanilla/bundle-splitting). Create React App does not include a specific code splitting solution. If you're just getting started, you might not consider code splitting at all. + +This means your app is shipped as a single bundle: + +```txt +- bundle.js 75kb +``` + +But for ideal performance, you should "split" your code into separate bundles so the user only needs to download what they need. This decreases the time the user needs to wait to load your app, by only downloading the code they need to see the page they are on. + +```txt +- core.js 25kb +- home.js 25kb +- dashboard.js 25kb +``` + +One way to do code-splitting is with `React.lazy`. However, this means that the code is not fetched until the component renders, which can cause network waterfalls. A more optimal solution is to use a router feature that fetches the code in parallel while the code is downloading. For example, React Router provides a `lazy` option to specify that a route should be code split and optimize when it is loaded: + +```js +import Home from './Home'; +import Dashboard from './Dashboard'; + +// ✅ Routes are downloaded before rendering +const router = createBrowserRouter([ + {path: '/', lazy: () => import('./Home')}, + {path: '/dashboard', lazy: () => import('Dashboard')} +]); +``` + +Optimized code-splitting is tricky to get right, and it's easy to make mistakes that can cause the user to download more code than they need. It works best when integrated with your router and data loading solutions to maximize caching, parallelize fetches, and support ["import on interaction"](https://www.patterns.dev/vanilla/import-on-interaction) patterns. + +### And more... {/*and-more*/} + +These are just a few examples of the limitations of Create React App. + +Once you've integrated routing, data-fetching, and code splitting, you now also need to consider pending states, navigation interruptions, error messages to the user, and revalidation of the data. There are entire categories of problems that users need to solve like: + +
+
    +
  • Accessibility
    • +
  • Asset loading
    • +
  • Authentication
    • +
  • Caching
    • +
+
    +
  • Error handling
    • +
  • Mutating data
    • +
  • Navigations
    • +
  • Optimistic updates
    • +
+
    +
  • Progressive enhancement
    • +
  • Server-side rendering
    • +
  • Static site generation
    • +
  • Streaming
    • +
+
+ +All of these work together to create the most optimal [loading sequence](https://www.patterns.dev/vanilla/loading-sequence). + +Solving each of these problems individually in Create React App can be difficult as each problem is interconnected with the others and can require deep expertise in problem areas users may not be familiar with. In order to solve these problems, users end up building their own bespoke solutions on top of Create React App, which was the problem Create React App originally tried to solve. + +## Why we Recommend Frameworks {/*why-we-recommend-frameworks*/} + +Although you could solve all these pieces yourself in a build tool like Create React App, Vite, or Parcel, it is hard to do well. Just like when Create React App itself integrated several build tools together, you need a tool to integrate all of these features together to provide the best experience to users. + +This category of tools that integrates build tools, rendering, routing, data fetching, and code splitting are known as "frameworks" -- or if you prefer to call React itself a framework, you might call them "metaframeworks". + +Frameworks impose some opinions about structuring your app in order to provide a much better user experience, in the same way build tools impose some opinions to make tooling easier. This is why we started recommending frameworks like [Next.js](https://nextjs.org/), [React Router](https://reactrouter.com/), and [Expo](https://expo.dev/) for new projects. + +Frameworks provide the same getting started experience as Create React App, but also provide solutions to problems users need to solve anyway in real production apps. + + + +#### Server rendering is optional {/*server-rendering-is-optional*/} + +The frameworks we recommend all provide the option to create a [client-side rendered (CSR)](https://developer.mozilla.org/en-US/docs/Glossary/CSR) app. + +In some cases, CSR is the right choice for a page, but many times it's not. Even if most of your app is client-side, there are often individual pages that could benefit from server rendering features like [static-site generation (SSG)](https://developer.mozilla.org/en-US/docs/Glossary/SSG) or [server-side rendering (SSR)](https://developer.mozilla.org/en-US/docs/Glossary/SSR), for example a Terms of Service page, or documentation. + +Server rendering generally sends less JavaScript to the client, and a full HTML document which produces a faster [First Contentful Paint (FCP)](https://web.dev/articles/fcp) by reducing [Total Blocking Time (TBD)](https://web.dev/articles/tbt), which can also lower [Interaction to Next Paint (INP)](https://web.dev/articles/inp). This is why the [Chrome team has encouraged](https://web.dev/articles/rendering-on-the-web) developers to consider static or server-side render over a full client-side approach to achieve the best possible performance. + +There are tradeoffs to using a server, and it is not always the best option for every page. Generating pages on the server incurs additional cost and takes time to generate which can increase [Time to First Byte (TTFB)](https://web.dev/articles/ttfb). The best performing apps are able to pick the right rendering strategy on a per-page basis, based on the tradeoffs of each strategy. + +Frameworks provide the option to use a server on any page if you want to, but do not force you to use a server. This allows you to pick the right rendering strategy for each page in your app. + +#### What About Server Components {/*server-components*/} + +The frameworks we recommend also include support for React Server Components. + +Server Components help solve these problems by moving routing and data fetching to the server, and allowing code splitting to be done for client components based on the data you render, instead of just the route rendered, and reducing the amount of JavaScript shipped for the best possible [loading sequence](https://www.patterns.dev/vanilla/loading-sequence). + +Server Components do not require a server. They can be run at build time on your CI server to create a static-site generated app (SSG) app, at runtime on a web server for a server-side rendered (SSR) app. + +See [Introducing zero-bundle size React Server Components](/blog/2020/12/21/data-fetching-with-react-server-components) and [the docs](/reference/rsc/server-components) for more info. + + + + + +#### Server Rendering is not just for SEO {/*server-rendering-is-not-just-for-seo*/} + +A common misunderstanding is that server rendering is only for [SEO](https://developer.mozilla.org/en-US/docs/Glossary/SEO). + +While server rendering can improve SEO, it also improves performance by reducing the amount of JavaScript the user needs to download and parse before they can see the content on the screen. + +This is why the Chrome team [has encouraged](https://web.dev/articles/rendering-on-the-web) developers to consider static or server-side render over a full client-side approach to achieve the best possible performance. + + + +--- + +_Thank you to [Dan Abramov](https://bsky.app/profile/danabra.mov) for creating Create React App, and [Joe Haddad](https://github.com/Timer), [Ian Schmitz](https://github.com/ianschmitz), [Brody McKee](https://github.com/mrmckeb), and [many others](https://github.com/facebook/create-react-app/graphs/contributors) for maintaining Create React App over the years. Thank you to [Brooks Lybrand](https://bsky.app/profile/brookslybrand.bsky.social), [Dan Abramov](https://bsky.app/profile/danabra.mov), [Devon Govett](https://bsky.app/profile/devongovett.bsky.social), [Eli White](https://x.com/Eli_White), [Jack Herrington](https://bsky.app/profile/jherr.dev), [Joe Savona](https://x.com/en_JS), [Lauren Tan](https://bsky.app/profile/no.lol), [Lee Robinson](https://x.com/leeerob), [Mark Erikson](https://bsky.app/profile/acemarke.dev), [Ryan Florence](https://x.com/ryanflorence), [Sophie Alpert](https://bsky.app/profile/sophiebits.com), [Tanner Linsley](https://bsky.app/profile/tannerlinsley.com), and [Theo Browne](https://x.com/theo) for reviewing and providing feedback on this post._ + diff --git a/src/content/blog/index.md b/src/content/blog/index.md index cc50b83c0..f7bbe76f3 100644 --- a/src/content/blog/index.md +++ b/src/content/blog/index.md @@ -4,12 +4,20 @@ title: React Blog -This blog is the official source for the updates from the React team. Anything important, including release notes or deprecation notices, will be posted here first. You can also follow the [@reactjs](https://twitter.com/reactjs) account on Twitter, but you won’t miss anything essential if you only read this blog. +This blog is the official source for the updates from the React team. Anything important, including release notes or deprecation notices, will be posted here first. + +You can also follow the [@react.dev](https://bsky.app/profile/react.dev) account on Bluesky, or [@reactjs](https://twitter.com/reactjs) account on Twitter, but you won’t miss anything essential if you only read this blog.
+ + +Today, we’re deprecating Create React App for new apps, and encouraging existing apps to migrate to a framework, or to migrate to a build tool like Vite, Parcel, or RSBuild. We’re also providing docs for when a framework isn’t a good fit for your project, you want to build your own framework, or you just want to learn how React works by building a React app from scratch ... + + + In the React 19 Upgrade Guide, we shared step-by-step instructions for upgrading your app to React 19. In this post, we'll give an overview of the new features in React 19, and how you can adopt them ... diff --git a/src/content/community/acknowledgements.md b/src/content/community/acknowledgements.md index 760076d83..bfe67f55a 100644 --- a/src/content/community/acknowledgements.md +++ b/src/content/community/acknowledgements.md @@ -36,6 +36,8 @@ We'd like to recognize a few people who have made significant contributions to R * [Joe Critchley](https://github.com/joecritch) * [Jeff Morrison](https://github.com/jeffmo) * [Luna Ruan](https://github.com/lunaruan) +* [Luna Wei](https://github.com/lunaleaps) +* [Noah Lemen](https://github.com/noahlemen) * [Kathryn Middleton](https://github.com/kmiddleton14) * [Keyan Zhang](https://github.com/keyz) * [Marco Salazar](https://github.com/salazarm) @@ -51,9 +53,10 @@ We'd like to recognize a few people who have made significant contributions to R * [Samuel Susla](https://github.com/sammy-SC) * [Sander Spies](https://github.com/sanderspies) * [Sasha Aickin](https://github.com/aickin) -* [Sean Keegan](https://github.com/seanryankeegan) +* [Sathya Gunasekaran](https://github.com/gsathya) * [Sophia Shoemaker](https://github.com/mrscobbler) * [Sunil Pai](https://github.com/threepointone) +* [Tianyu Yao](https://github.com/) * [Tim Yung](https://github.com/yungsters) * [Xuan Huang](https://github.com/huxpro) diff --git a/src/content/community/conferences.md b/src/content/community/conferences.md index ff0803c56..7a19a2e8f 100644 --- a/src/content/community/conferences.md +++ b/src/content/community/conferences.md @@ -11,20 +11,49 @@ Do you know of a local React.js conference? Add it here! (Please keep the list c ## Upcoming Conferences {/*upcoming-conferences*/} ### React Paris 2025 {/*react-paris-2025*/} +<<<<<<< HEAD March 20 - 21, 2024. In-person in Paris, France (hybrid event) [Website](https://react.paris/) - [Twitter](https://x.com/BeJS_) +======= +March 20 - 21, 2025. In-person in Paris, France (hybrid event) + +[Website](https://react.paris/) - [Twitter](https://x.com/BeJS_) + +### React Native Connection 2025 {/*react-native-connection-2025*/} +April 3 (Reanimated Training) + April 4 (Conference), 2025. Paris, France. + +[Website](https://reactnativeconnection.io/) - [X](https://x.com/reactnativeconn) - [Bluesky](https://bsky.app/profile/reactnativeconnect.bsky.social) + +### CityJS London 2025 {/*cityjs-london*/} +April 23 - 25, 2025. In-person in London, UK + +[Website](https://london.cityjsconf.org/) - [Twitter](https://x.com/cityjsconf) - [Bluesky](https://bsky.app/profile/cityjsconf.bsky.social) +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff ### App.js Conf 2025 {/*appjs-conf-2025*/} May 28 - 30, 2025. In-person in Kraków, Poland + remote [Website](https://appjs.co) - [Twitter](https://twitter.com/appjsconf) +### CityJS Athens 2025 {/*cityjs-athens*/} +May 27 - 31, 2025. In-person in Athens, Greece + +[Website](https://athens.cityjsconf.org/) - [Twitter](https://x.com/cityjsconf) - [Bluesky](https://bsky.app/profile/cityjsconf.bsky.social) + ### React Summit 2025 {/*react-summit-2025*/} June 13 - 17, 2025. In-person in Amsterdam, Netherlands + remote (hybrid event) [Website](https://reactsummit.com/) - [Twitter](https://x.com/reactsummit) +<<<<<<< HEAD +======= +### React Nexus 2025 {/*react-nexus-2025*/} +July 03 - 05, 2025. In-person in Bangalore, India + +[Website](https://reactnexus.com/) - [Twitter](https://x.com/ReactNexus) - [Bluesky](https://bsky.app/profile/reactnexus.com) - [Linkedin](https://www.linkedin.com/company/react-nexus) - [YouTube](https://www.youtube.com/reactify_in) + +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff ### React Universe Conf 2025 {/*react-universe-conf-2025*/} September 2-4, 2025. Wrocław, Poland. diff --git a/src/content/community/meetups.md b/src/content/community/meetups.md index 14097aa4d..906c170de 100644 --- a/src/content/community/meetups.md +++ b/src/content/community/meetups.md @@ -57,6 +57,9 @@ Do you have a local React.js meetup? Add it here! (Please keep the list alphabet * [React Advanced London](https://guild.host/react-advanced-london) * [React Native London](https://guild.host/RNLDN) +## Finland {/*finland*/} +* [Helsinki](https://www.meetabit.com/communities/react-helsinki) + ## France {/*france*/} * [Lille](https://www.meetup.com/ReactBeerLille/) * [Paris](https://www.meetup.com/ReactJS-Paris/) @@ -136,6 +139,9 @@ Do you have a local React.js meetup? Add it here! (Please keep the list alphabet ## Spain {/*spain*/} * [Barcelona](https://www.meetup.com/ReactJS-Barcelona/) +## Sri Lanka {/*sri-lanka*/} +* [Colombo](https://www.javascriptcolombo.com/) + ## Sweden {/*sweden*/} * [Goteborg](https://www.meetup.com/ReactJS-Goteborg/) * [Stockholm](https://www.meetup.com/Stockholm-ReactJS-Meetup/) diff --git a/src/content/community/team.md b/src/content/community/team.md index 94f31f09f..da4ce0791 100644 --- a/src/content/community/team.md +++ b/src/content/community/team.md @@ -22,10 +22,14 @@ Current members of the React team are listed in alphabetical order below. Dan got into programming after he accidentally discovered Visual Basic inside Microsoft PowerPoint. He has found his true calling in turning [Sebastian](#sebastian-markbåge)'s tweets into long-form blog posts. Dan occasionally wins at Fortnite by hiding in a bush until the game ends. - + Eli got into programming after he got suspended from middle school for hacking. He has been working on React and React Native since 2017. He enjoys eating treats, especially ice cream and apple pie. You can find Eli trying quirky activities like parkour, indoor skydiving, and aerial silks. + + Hendrik’s journey in tech started in the late 90s when he built his first websites with Netscape Communicator. After earning a diploma in computer science and working at digital agencies, he built a React Server Components bundler and library, paving the way to his role on the Next.js team. Outside of work, he enjoys cycling and tinkering in his workshop. + + Shortly after being introduced to AutoHotkey, Jack had written scripts to automate everything he could think of. When reaching limitations there, he dove headfirst into web app development and hasn't looked back. Most recently, Jack worked on the web platform at Instagram before moving to React. His favorite programming language is JSX. @@ -38,6 +42,10 @@ Current members of the React team are listed in alphabetical order below. Joe was planning to major in math and philosophy but got into computer science after writing physics simulations in Matlab. Prior to React, he worked on Relay, RSocket.js, and the Skip programming language. While he’s not building some sort of reactive system he enjoys running, studying Japanese, and spending time with his family. + + Jordan started coding by building iPhone apps, where he was pushing and popping view controllers before he knew that for-loops were a thing. He enjoys working on technology that developers love, which naturally drew him to React. Outside of work he enjoys reading, kiteboarding, and playing guitar. + + Josh majored in Mathematics and discovered programming while in college. His first professional developer job was to program insurance rate calculations in Microsoft Excel, the paragon of Reactive Programming which must be why he now works on React. In between that time Josh has been an IC, Manager, and Executive at a few startups. outside of work he likes to push his limits with cooking. @@ -46,20 +54,20 @@ Current members of the React team are listed in alphabetical order below. Lauren's programming career peaked when she first discovered the `` tag. She’s been chasing that high ever since. She studied Finance instead of CS in college, so she learned to code using Excel. Lauren enjoys dropping cheeky memes in chat, playing video games with her partner, learning Korean, and petting her dog Zelda. - - Luna first learnt the fundamentals of python at the age of 6 from her father. Since then, she has been unstoppable. Luna aspires to be a gen z, and the road to success is paved with environmental advocacy, urban gardening and lots of quality time with her Voo-Doo’d (as pictured). - - Matt stumbled into coding, and since then, has become enamored with creating things in communities that can’t be created alone. Prior to React, he worked on YouTube, the Google Assistant, Fuchsia, and Google Cloud AI and Evernote. When he's not trying to make better developer tools he enjoys the mountains, jazz, and spending time with his family. + + Mike went to grad school dreaming of becoming a professor but realized that he liked building things a lot more than writing grant applications. Mike joined Meta to work on Javascript infrastructure, which ultimately led him to work on the React Compiler. When not hacking on either Javascript or OCaml, Mike can often be found hiking or skiing in the Pacific Northwest. + + Mofei started programming when she realized it can help her cheat in video games. She focused on operating systems in undergrad / grad school, but now finds herself happily tinkering on React. Outside of work, she enjoys debugging bouldering problems and planning her next backpacking trip(s). - - Noah’s interest in UI programming sparked during his education in music technology at NYU. At Meta, he's worked on internal tools, browsers, web performance, and is currently focused on React. Outside of work, Noah can be found tinkering with synthesizers or spending time with his cat. + + Pieter studied building science but after failing to get a job he made himself a website and things escalated from there. At Meta, he enjoys working on performance, languages and now React. When he's not programming you can find him off-road in the mountains. @@ -70,10 +78,6 @@ Current members of the React team are listed in alphabetical order below. Ruslan's introduction to UI programming started when he was a kid by manually editing HTML templates for his custom gaming forums. Somehow, he ended up majoring in Computer Science. He enjoys music, games, and memes. Mostly memes. - - Sathya hated the Dragon Book in school but somehow ended up working on compilers all his career. When he's not compiling React components, he's either drinking coffee or eating yet another Dosa. - - Sebastian majored in psychology. He's usually quiet. Even when he says something, it often doesn't make sense to the rest of us until a few months later. The correct way to pronounce his surname is "mark-boa-geh" but he settled for "mark-beige" out of pragmatism -- and that's how he approaches React. @@ -90,10 +94,6 @@ Current members of the React team are listed in alphabetical order below. Four days after React was released, Sophie rewrote the entirety of her then-current project to use it, which she now realizes was perhaps a bit reckless. After she became the project's #1 committer, she wondered why she wasn't getting paid by Facebook like everyone else was and joined the team officially to lead React through its adolescent years. Though she quit that job years ago, somehow she's still in the team's group chats and “providing value”. - - Tianyu’s interest in computers started as a kid because he loves video games. So he majored in computer science and still plays childish games like League of Legends. When he is not in front of a computer, he enjoys playing with his two kittens, hiking and kayaking. - - Yuzhi studied Computer Science in school. She liked the instant gratification of seeing code come to life without having to physically be in a laboratory. Now she’s a manager in the React org. Before management, she used to work on the Relay data fetching framework. In her spare time, Yuzhi enjoys optimizing her life via gardening and home improvement projects. diff --git a/src/content/community/versioning-policy.md b/src/content/community/versioning-policy.md index 7aa71efd2..a61d19942 100644 --- a/src/content/community/versioning-policy.md +++ b/src/content/community/versioning-policy.md @@ -8,7 +8,7 @@ All stable builds of React go through a high level of testing and follow semanti -For a list of previous releases, see the [Versions](/versions) page. +This versioning policy describes our approach to version numbers for packages such as `react` and `react-dom`. For a list of previous releases, see the [Versions](/versions) page. ## Stable releases {/*stable-releases*/} @@ -24,7 +24,9 @@ Major releases can also contain new features, and any release can include bug fi Minor releases are the most common type of release. -### Breaking Changes {/*breaking-changes*/} +We know our users continue to use old versions of React in production. If we learn of a security vulnerability in React, we release a backported fix for all major versions that are affected by the vulnerability. + +### Breaking changes {/*breaking-changes*/} Breaking changes are inconvenient for everyone, so we try to minimize the number of major releases – for example, React 15 was released in April 2016 and React 16 was released in September 2017, and React 17 was released in October 2020. diff --git a/src/content/learn/add-react-to-an-existing-project.md b/src/content/learn/add-react-to-an-existing-project.md index 0457d0cfc..25c87311b 100644 --- a/src/content/learn/add-react-to-an-existing-project.md +++ b/src/content/learn/add-react-to-an-existing-project.md @@ -20,9 +20,15 @@ title: 將 React 加入到一個現有的專案 以下是我們推薦的設定方式： +<<<<<<< HEAD 1. 使用其中一個[基於 React 的框架]((/learn/start-a-new-react-project))來**建構你的應用程式中的 React 部分**。 2. 在你的框架設定中將 **`/some-app` 指定為 *基本路徑***（這裡是如何設定：[Next.js](https://nextjs.org/docs/app/api-reference/config/next-config-js/basePath)、[Gatsby](https://www.gatsbyjs.com/docs/how-to/previews-deploys-hosting/path-prefix/))。 3. **設定你的伺服器或代理**，讓所有在 `/some-app/` 下的請求都由 React 應用程式處理。 +======= +1. **Build the React part of your app** using one of the [React-based frameworks](/learn/start-a-new-react-project). +2. **Specify `/some-app` as the *base path*** in your framework's configuration (here's how: [Next.js](https://nextjs.org/docs/app/api-reference/config/next-config-js/basePath), [Gatsby](https://www.gatsbyjs.com/docs/how-to/previews-deploys-hosting/path-prefix/)). +3. **Configure your server or a proxy** so that all requests under `/some-app/` are handled by your React app. +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff 這可以確保你的應用程式中 React 部分能夠[受益於這些框架所內建的最佳實踐](/learn/start-a-new-react-project#can-i-use-react-without-a-framework)。 @@ -45,7 +51,11 @@ title: 將 React 加入到一個現有的專案 * **如果你的應用程式已經拆分成使用 `import` 語句的檔案**，請嘗試使用你已經設定好的設定。檢查在你的 JS 程式碼中寫入 `
` 是否會導致語法錯誤。如果它導致了語法錯誤，則可能需要[使用 Babel 轉換你的 JavaScript 程式碼](https://babeljs.io/setup)，並啟用 [Babel React preset](https://babeljs.io/docs/babel-preset-react) 來使用 JSX。 +<<<<<<< HEAD * **如果你的應用程式沒有現有的 JavaScript module 的編譯設定**，請使用 [Vite](https://vitejs.dev/) 進行設定。Vite 社群維護[與後端框架的多個整合](https://github.com/vitejs/awesome-vite#integrations-with-backends)，包括 Rails、Django 和 Laravel。如果你的後端框架未被列出，請按照此指南[手動將 Vite 建構與你的後端整合](https://vitejs.dev/guide/backend-integration.html)。 +======= +* **If your app doesn't have an existing setup for compiling JavaScript modules,** set it up with [Vite](https://vite.dev/). The Vite community maintains [many integrations with backend frameworks](https://github.com/vitejs/awesome-vite#integrations-with-backends), including Rails, Django, and Laravel. If your backend framework is not listed, [follow this guide](https://vite.dev/guide/backend-integration.html) to manually integrate Vite builds with your backend. +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff 為了檢查你的設定是否正常運作，請在你的專案資料夾中執行此命令： @@ -85,7 +95,11 @@ root.render(

Hello, world

); +<<<<<<< HEAD 將一個模組化的 JavaScript 環境整合到現有專案中，對於第一次嘗試的人來說可能會感到令人生畏，但它是值得的！如果你卡住了，請嘗試使用我們的[社群資源](/community)或 [Vite Chat](https://chat.vitejs.dev/)。 +======= +Integrating a modular JavaScript environment into an existing project for the first time can feel intimidating, but it's worth it! If you get stuck, try our [community resources](/community) or the [Vite Chat](https://chat.vite.dev/). +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff diff --git a/src/content/learn/build-a-react-app-from-scratch.md b/src/content/learn/build-a-react-app-from-scratch.md new file mode 100644 index 000000000..e5b396c7e --- /dev/null +++ b/src/content/learn/build-a-react-app-from-scratch.md @@ -0,0 +1,143 @@ +--- +title: Build a React app from Scratch +--- + + + +If your app has constraints not well-served by existing frameworks, you prefer to build your own framework, or you just want to learn the basics of a React app, you can build a React app from scratch. + + + + + +#### Consider using a framework {/*consider-using-a-framework*/} + +Starting from scratch is an easy way to get started using React, but a major tradeoff to be aware of is that going this route is often the same as building your own adhoc framework. As your requirements evolve, you may need to solve more framework-like problems that our recommended frameworks already have well developed and supported solutions for. + +For example, if in the future your app needs support for server-side rendering (SSR), static site generation (SSG), and/or React Server Components (RSC), you will have to implement those on your own. Similarly, future React features that require integrating at the framework level will have to be implemented on your own if you want to use them. + +Our recommended frameworks also help you build better performing apps. For example, reducing or eliminating waterfalls from network requests makes for a better user experience. This might not be a high priority when you are building a toy project, but if your app gains users you may want to improve its performance. + +Going this route also makes it more difficult to get support, since the way you develop routing, data-fetching, and other features will be unique to your situation. You should only choose this option if you are comfortable tackling these problems on your own, or if you’re confident that you will never need these features. + +For a list of recommended frameworks, check out [Creating a React App](/learn/creating-a-react-app). + + + + +## Step 1: Install a build tool {/*step-1-install-a-build-tool*/} + +The first step is to install a build tool like `vite`, `parcel`, or `rsbuild`. These build tools provide features to package and run source code, provide a development server for local development and a build command to deploy your app to a production server. + +### Vite {/*vite*/} + +[Vite](https://vite.dev/) is a build tool that aims to provide a faster and leaner development experience for modern web projects. + + +{`npm create vite@latest my-app -- --template react`} + + +Vite is opinionated and comes with sensible defaults out of the box. Vite has a rich ecosystem of plugins to support fast refresh, JSX, Babel/SWC, and other common features. See Vite's [React plugin](https://vite.dev/plugins/#vitejs-plugin-react) or [React SWC plugin](https://vite.dev/plugins/#vitejs-plugin-react-swc) and [React SSR example project](https://vite.dev/guide/ssr.html#example-projects) to get started. + +Vite is already being used as a build tool in one of our [recommended frameworks](/learn/creating-a-react-app): [React Router](https://reactrouter.com/start/framework/installation). + +### Parcel {/*parcel*/} + +[Parcel](https://parceljs.org/) combines a great out-of-the-box development experience with a scalable architecture that can take your project from just getting started to massive production applications. + + +{`npm install --save-dev parcel`} + + +Parcel supports fast refresh, JSX, TypeScript, Flow, and styling out of the box. See [Parcel's React recipe](https://parceljs.org/recipes/react/#getting-started) to get started. + +### Rsbuild {/*rsbuild*/} + +[Rsbuild](https://rsbuild.dev/) is an Rspack-powered build tool that provides a seamless development experience for React applications. It comes with carefully tuned defaults and performance optimizations ready to use. + + +{`npx create-rsbuild --template react`} + + +Rsbuild includes built-in support for React features like fast refresh, JSX, TypeScript, and styling. See [Rsbuild's React guide](https://rsbuild.dev/guide/framework/react) to get started. + + + +#### Metro for React Native {/*react-native*/} + +If you'd you're starting from scratch with React Native you'll need to use [Metro](https://metrobundler.dev/), the JavaScript bundler for React Native. Metro supports bundling for platforms like iOS and Android, but lacks many features when compared to the tools here. We recommend starting with Vite, Parcel, or Rsbuild unless your project requires React Native support. + + + +## Step 2: Build Common Application Patterns {/*step-2-build-common-application-patterns*/} + +The build tools listed above start off with a client-only, single-page app (SPA), but don't include any further solutions for common functionality like routing, data fetching, or styling. + +The React ecosystem includes many tools for these problems. We've listed a few that are widely used as a starting point, but feel free to choose other tools if those work better for you. + +### Routing {/*routing*/} + +Routing determines what content or pages to display when a user visits a particular URL. You need to set up a router to map URLs to different parts of your app. You'll also need to handle nested routes, route parameters, and query parameters. Routers can be configured within your code, or defined based on your component folder and file structures. + +Routers are a core part of modern applications, and are usually integrated with data fetching (including prefetching data for a whole page for faster loading), code splitting (to minimize client bundle sizes), and page rendering approaches (to decide how each page gets generated). + +We suggest using: + +- [React Router](https://reactrouter.com/start/framework/custom) +- [Tanstack Router](https://tanstack.com/router/latest) + + +### Data Fetching {/*data-fetching*/} + +Fetching data from a server or other data source is a key part of most applications. Doing this properly requires handling loading states, error states, and caching the fetched data, which can be complex. + +Purpose-built data fetching libraries do the hard work of fetching and caching the data for you, letting you focus on what data your app needs and how to display it. These libraries are typically used directly in your components, but can also be integrated into routing loaders for faster pre-fetching and better performance, and in server rendering as well. + +Note that fetching data directly in components can lead to slower loading times due to network request waterfalls, so we recommend prefetching data in router loaders or on the server as much as possible! This allows a page's data to be fetched all at once as the page is being displayed. + +If you're fetching data from most backends or REST-style APIs, we suggest using: + +- [React Query](https://react-query.tanstack.com/) +- [SWR](https://swr.vercel.app/) +- [RTK Query](https://redux-toolkit.js.org/rtk-query/overview) + +If you're fetching data from a GraphQL API, we suggest using: + +- [Apollo](https://www.apollographql.com/docs/react) +- [Relay](https://relay.dev/) + + +### Code-splitting {/*code-splitting*/} + +Code-splitting is the process of breaking your app into smaller bundles that can be loaded on demand. An app's code size increases with every new feature and additional dependency. Apps can become slow to load because all of the code for the entire app needs to be sent before it can be used. Caching, reducing features/dependencies, and moving some code to run on the server can help mitigate slow loading but are incomplete solutions that can sacrifice functionality if overused. + +Similarly, if you rely on the apps using your framework to split the code, you might encounter situations where loading becomes slower than if no code splitting were happening at all. For example, [lazily loading](/reference/react/lazy) a chart delays sending the code needed to render the chart, splitting the chart code from the rest of the app. [Parcel supports code splitting with React.lazy](https://parceljs.org/recipes/react/#code-splitting). However, if the chart loads its data *after* it has been initially rendered you are now waiting twice. This is a waterfall: rather than fetching the data for the chart and sending the code to render it simultaneously, you must wait for each step to complete one after the other. + +Splitting code by route, when integrated with bundling and data fetching, can reduce the initial load time of your app and the time it takes for the largest visible content of the app to render ([Largest Contentful Paint](https://web.dev/articles/lcp)). + +For code-splitting instructions, see your build tool docs: +- [Vite build optimizations](https://v3.vitejs.dev/guide/features.html#build-optimizations) +- [Parcel code splitting](https://parceljs.org/features/code-splitting/) +- [Rsbuild code splitting](https://rsbuild.dev/guide/optimization/code-splitting) + +### Improving Application Performance {/*improving-application-performance*/} + +Since the build tool you select only support single page apps (SPAs) you'll need to implement other [rendering patterns](https://www.patterns.dev/vanilla/rendering-patterns) like server-side rendering (SSR), static site generation (SSG), and/or React Server Components (RSC). Even if you don't need these features at first, in the future there may be some routes that would benefit SSR, SSG or RSC. + +* **Single-page apps (SPA)** load a single HTML page and dynamically updates the page as the user interacts with the app. SPAs are easier to get started with, but they can have slower initial load times. SPAs are the default architecture for most build tools. + +* **Streaming Server-side rendering (SSR)** renders a page on the server and sends the fully rendered page to the client. SSR can improve performance, but it can be more complex to set up and maintain than a single-page app. With the addition of streaming, SSR can be very complex to set up and maintain. See [Vite's SSR guide]( https://vite.dev/guide/ssr). + +* **Static site generation (SSG)** generates static HTML files for your app at build time. SSG can improve performance, but it can be more complex to set up and maintain than server-side rendering. See [Vite's SSG guide](https://vite.dev/guide/ssr.html#pre-rendering-ssg). + +* **React Server Components (RSC)** lets you mix build-time, server-only, and interactive components in a single React tree. RSC can improve performance, but it currently requires deep expertise to set up and maintain. See [Parcel's RSC examples](https://github.com/parcel-bundler/rsc-examples). + +Your rendering strategies need to integrate with your router so apps built with your framework can choose the rendering strategy on a per-route level. This will enable different rendering strategies without having to rewrite your whole app. For example, the landing page for your app might benefit from being statically generated (SSG), while a page with a content feed might perform best with server-side rendering. + +Using the right rendering strategy for the right routes can decrease the time it takes for the first byte of content to be loaded ([Time to First Byte](https://web.dev/articles/ttfb)), the first piece of content to render ([First Contentful Paint](https://web.dev/articles/fcp)), and the largest visible content of the app to render ([Largest Contentful Paint](https://web.dev/articles/lcp)). + +### And more... {/*and-more*/} + +These are just a few examples of the features a new app will need to consider when building from scratch. Many limitations you'll hit can be difficult to solve as each problem is interconnected with the others and can require deep expertise in problem areas you may not be familiar with. + +If you don't want to solve these problems on your own, you can [get started with a framework](/learn/creating-a-react-app) that provides these features out of the box. diff --git a/src/content/learn/creating-a-react-app.md b/src/content/learn/creating-a-react-app.md new file mode 100644 index 000000000..fc6c956d4 --- /dev/null +++ b/src/content/learn/creating-a-react-app.md @@ -0,0 +1,113 @@ +--- +title: Creating a React App +--- + + + +If you want to build a new app or website with React, we recommend starting with a framework. + + + +If your app has constraints not well-served by existing frameworks, you prefer to build your own framework, or you just want to learn the basics of a React app, you can [build a React app from scratch](/learn/build-a-react-app-from-scratch). + +## Full-stack frameworks {/*full-stack-frameworks*/} + +These recommended frameworks support all the features you need to deploy and scale your app in production. They have integrated the latest React features and take advantage of React’s architecture. + + + +#### Full-stack frameworks do not require a server. {/*react-frameworks-do-not-require-a-server*/} + +All the frameworks on this page support client-side rendering ([CSR](https://developer.mozilla.org/en-US/docs/Glossary/CSR)), single-page apps ([SPA](https://developer.mozilla.org/en-US/docs/Glossary/SPA)), and static-site generation ([SSG](https://developer.mozilla.org/en-US/docs/Glossary/SSG)). These apps can be deployed to a [CDN](https://developer.mozilla.org/en-US/docs/Glossary/CDN) or static hosting service without a server. Additionally, these frameworks allow you to add server-side rendering on a per-route basis, when it makes sense for your use case. + +This allows you to start with a client-only app, and if your needs change later, you can opt-in to using server features on individual routes without rewriting your app. See your framework's documentation for configuring the rendering strategy. + + + +### Next.js (App Router) {/*nextjs-app-router*/} + +**[Next.js's App Router](https://nextjs.org/docs) is a React framework that takes full advantage of React's architecture to enable full-stack React apps.** + + +npx create-next-app@latest + + +Next.js is maintained by [Vercel](https://vercel.com/). You can [deploy a Next.js app](https://nextjs.org/docs/app/building-your-application/deploying) to any Node.js or serverless hosting, or to your own server. Next.js also supports [static export](https://nextjs.org/docs/app/building-your-application/deploying/static-exports) which doesn't require a server. Vercel additionally provides opt-in paid cloud services. + +### React Router (v7) {/*react-router-v7*/} + +**[React Router](https://reactrouter.com/start/framework/installation) is the most popular routing library for React and can be paired with Vite to create a full-stack React framework**. It emphasizes standard Web APIs and has several [ready to deploy templates](https://github.com/remix-run/react-router-templates) for various JavaScript runtimes and platforms. + +To create a new React Router framework project, run: + + +npx create-react-router@latest + + +React Router is maintained by [Shopify](https://www.shopify.com). + +### Expo (for native apps) {/*expo*/} + +**[Expo](https://expo.dev/) is a React framework that lets you create universal Android, iOS, and web apps with truly native UIs.** It provides an SDK for [React Native](https://reactnative.dev/) that makes the native parts easier to use. To create a new Expo project, run: + + +npx create-expo-app@latest + + +If you're new to Expo, check out the [Expo tutorial](https://docs.expo.dev/tutorial/introduction/). + +Expo is maintained by [Expo (the company)](https://expo.dev/about). Building apps with Expo is free, and you can submit them to the Google and Apple app stores without restrictions. Expo additionally provides opt-in paid cloud services. + + +## Other frameworks {/*other-frameworks*/} + +There are other up-and-coming frameworks that are working towards our full stack React vision: + +- [TanStack Start (Beta)](https://tanstack.com/): TanStack Start is a full-stack React framework powered by TanStack Router. It provides a full-document SSR, streaming, server functions, bundling, and more using tools like Nitro and Vite. +- [RedwoodJS](https://redwoodjs.com/): Redwood is a full stack React framework with lots of pre-installed packages and configuration that makes it easy to build full-stack web applications. + + + +#### Which features make up the React team’s full-stack architecture vision? {/*which-features-make-up-the-react-teams-full-stack-architecture-vision*/} + +Next.js's App Router bundler fully implements the official [React Server Components specification](https://github.com/reactjs/rfcs/blob/main/text/0188-server-components.md). This lets you mix build-time, server-only, and interactive components in a single React tree. + +For example, you can write a server-only React component as an `async` function that reads from a database or from a file. Then you can pass data down from it to your interactive components: + +```js +// This component runs *only* on the server (or during the build). +async function Talks({ confId }) { + // 1. You're on the server, so you can talk to your data layer. API endpoint not required. + const talks = await db.Talks.findAll({ confId }); + + // 2. Add any amount of rendering logic. It won't make your JavaScript bundle larger. + const videos = talks.map(talk => talk.video); + + // 3. Pass the data down to the components that will run in the browser. + return ; +} +``` + +Next.js's App Router also integrates [data fetching with Suspense](/blog/2022/03/29/react-v18#suspense-in-data-frameworks). This lets you specify a loading state (like a skeleton placeholder) for different parts of your user interface directly in your React tree: + +```js +}> + + +``` + +Server Components and Suspense are React features rather than Next.js features. However, adopting them at the framework level requires buy-in and non-trivial implementation work. At the moment, the Next.js App Router is the most complete implementation. The React team is working with bundler developers to make these features easier to implement in the next generation of frameworks. + + + +## Start From Scratch {/*start-from-scratch*/} + +If your app has constraints not well-served by existing frameworks, you prefer to build your own framework, or you just want to learn the basics of a React app, there are other options available for starting a React project from scratch. + +Starting from scratch gives you more flexibility, but does require that you make choices on which tools to use for routing, data fetching, and other common usage patterns. It's a lot like building your own framework, instead of using a framework that already exists. The [frameworks we recommend](#full-stack-frameworks) have built-in solutions for these problems. + +If you want to build your own solutions, see our guide to [build a React app from Scratch](/learn/build-a-react-app-from-scratch) for instructions on how to set up a new React project starting with a built tool like [Vite](https://vite.dev/), [Parcel](https://parceljs.org/), or [RSbuild](https://rsbuild.dev/). + +----- + +_If you’re a framework author interested in being included on this page, [please let us know](https://github.com/reactjs/react.dev/issues/new?assignees=&labels=type%3A+framework&projects=&template=3-framework.yml&title=%5BFramework%5D%3A+)._ diff --git a/src/content/learn/installation.md b/src/content/learn/installation.md index 47baee6c0..920482184 100644 --- a/src/content/learn/installation.md +++ b/src/content/learn/installation.md @@ -8,6 +8,7 @@ React 從一開始就被設計成可以逐步採用。你可以根據自己的 +<<<<<<< HEAD * [如何開始一個新的 React 專案](/learn/start-a-new-react-project) @@ -18,6 +19,9 @@ React 從一開始就被設計成可以逐步採用。你可以根據自己的 ## 嘗試 React {/*try-react*/} +======= +## Try React {/*try-react*/} +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff 你不需要安裝任何東西來嘗試 React。試試看編輯這個 sandbox！ @@ -39,6 +43,7 @@ export default function App() { React 文件中的大多數頁面都包含像這樣的 sandbox 範例。在 React 文件之外，有許多支援 React 的線上 sandbox，例如 [CodeSandbox](https://codesandbox.io/s/new)、[StackBlitz](https://stackblitz.com/fork/react) 或 [CodePen](https://codepen.io/pen?template=QWYVwWN)。 +<<<<<<< HEAD ### 在本機端嘗試 React {/*try-react-locally*/} 在你的電腦本機端嘗試 React，[下載這個 HTML 頁面。](https://gist.githubusercontent.com/gaearon/0275b1e1518599bbeafcde4722e79ed1/raw/db72dcbf3384ee1708c4a07d3be79860db04bff0/example.html) 在你的編輯器和瀏覽器打開它！ @@ -46,10 +51,34 @@ React 文件中的大多數頁面都包含像這樣的 sandbox 範例。在 Reac ## 開始一個新的 React 專案 {/*start-a-new-react-project*/} 如果你想要完全使用 React 建立一個應用程式或是網站，[開始一個新的 React 專案。](/learn/start-a-new-react-project) +======= +To try React locally on your computer, [download this HTML page.](https://gist.githubusercontent.com/gaearon/0275b1e1518599bbeafcde4722e79ed1/raw/db72dcbf3384ee1708c4a07d3be79860db04bff0/example.html) Open it in your editor and in your browser! + +## Creating a React App {/*creating-a-react-app*/} + +If you want to start a new React app, you can [create a React app](/learn/creating-a-react-app) using a recommended framework. + +## Build a React App from Scratch {/*build-a-react-app-from-scratch*/} + +If a framework is not a good fit for your project, you prefer to build your own framework, or you just want to learn the basics of a React app you can [build a React app from scratch](/learn/build-a-react-app-from-scratch). +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff ## 將 React 加入到一個現有的專案 {/*add-react-to-an-existing-project*/} +<<<<<<< HEAD 如果你想要在你現有的應用程式或網站嘗試使用 React，[將 React 加入到一個現有的專案。](/learn/add-react-to-an-existing-project) +======= +If want to try using React in your existing app or a website, you can [add React to an existing project.](/learn/add-react-to-an-existing-project) + + + + +#### Should I use Create React App? {/*should-i-use-create-react-app*/} + +No. Create React App has been deprecated. For more information, see [Sunsetting Create React App](/blog/2025/02/14/sunsetting-create-react-app). + + +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff ## 下一步 {/*next-steps*/} diff --git a/src/content/learn/manipulating-the-dom-with-refs.md b/src/content/learn/manipulating-the-dom-with-refs.md index e366ea7cc..2053f936b 100644 --- a/src/content/learn/manipulating-the-dom-with-refs.md +++ b/src/content/learn/manipulating-the-dom-with-refs.md @@ -647,7 +647,7 @@ However, this doesn't mean that you can't do it at all. It requires caution. **Y - Refs are a generic concept, but most often you'll use them to hold DOM elements. - You instruct React to put a DOM node into `myRef.current` by passing `
`. - Usually, you will use refs for non-destructive actions like focusing, scrolling, or measuring DOM elements. -- A component doesn't expose its DOM nodes by default. You can opt into exposing a DOM node by using `forwardRef` and passing the second `ref` argument down to a specific node. +- A component doesn't expose its DOM nodes by default. You can opt into exposing a DOM node by using the `ref` prop. - Avoid changing DOM nodes managed by React. - If you do modify DOM nodes managed by React, modify parts that React has no reason to update. @@ -1049,7 +1049,7 @@ Make it so that clicking the "Search" button puts focus into the field. Note tha -You'll need `forwardRef` to opt into exposing a DOM node from your own component like `SearchInput`. +You'll need to pass `ref` as a prop to opt into exposing a DOM node from your own component like `SearchInput`. @@ -1134,18 +1134,14 @@ export default function SearchButton({ onClick }) { ``` ```js src/SearchInput.js -import { forwardRef } from 'react'; - -export default forwardRef( - function SearchInput(props, ref) { - return ( - - ); - } -); +export default function SearchInput({ ref }) { + return ( + + ); +} ``` ```css diff --git a/src/content/learn/passing-data-deeply-with-context.md b/src/content/learn/passing-data-deeply-with-context.md index 1aea87b35..e81678c8e 100644 --- a/src/content/learn/passing-data-deeply-with-context.md +++ b/src/content/learn/passing-data-deeply-with-context.md @@ -468,15 +468,15 @@ import { LevelContext } from './LevelContext.js'; export default function Section({ level, children }) { return (
- + {children} - +
); } ``` -This tells React: "if any component inside this `
` asks for `LevelContext`, give them this `level`." The component will use the value of the nearest `` in the UI tree above it. +This tells React: "if any component inside this `
` asks for `LevelContext`, give them this `level`." The component will use the value of the nearest `` in the UI tree above it. @@ -514,9 +514,9 @@ import { LevelContext } from './LevelContext.js'; export default function Section({ level, children }) { return (
- + {children} - +
); } @@ -567,7 +567,7 @@ export const LevelContext = createContext(1); It's the same result as the original code, but you did not need to pass the `level` prop to each `Heading` component! Instead, it "figures out" its heading level by asking the closest `Section` above: 1. You pass a `level` prop to the `
`. -2. `Section` wraps its children into ``. +2. `Section` wraps its children into ``. 3. `Heading` asks the closest value of `LevelContext` above with `useContext(LevelContext)`. ## Using and providing context from the same component {/*using-and-providing-context-from-the-same-component*/} @@ -595,9 +595,9 @@ export default function Section({ children }) { const level = useContext(LevelContext); return (
- + {children} - +
); } @@ -643,9 +643,9 @@ export default function Section({ children }) { const level = useContext(LevelContext); return (
- + {children} - +
); } @@ -776,9 +776,9 @@ export default function Section({ children, isFancy }) { 'section ' + (isFancy ? 'fancy' : '') }> - + {children} - +
); } @@ -868,7 +868,7 @@ In general, if some information is needed by distant components in different par * To pass context: 1. Create and export it with `export const MyContext = createContext(defaultValue)`. 2. Pass it to the `useContext(MyContext)` Hook to read it in any child component, no matter how deep. - 3. Wrap children into `` to provide it from a parent. + 3. Wrap children into `` to provide it from a parent. * Context passes through any components in the middle. * Context lets you write components that "adapt to their surroundings". * Before you use context, try passing props or passing JSX as `children`. @@ -1022,7 +1022,7 @@ li { Remove `imageSize` prop from all the components. -Create and export `ImageSizeContext` from `Context.js`. Then wrap the List into `` to pass the value down, and `useContext(ImageSizeContext)` to read it in the `PlaceImage`: +Create and export `ImageSizeContext` from `Context.js`. Then wrap the List into `` to pass the value down, and `useContext(ImageSizeContext)` to read it in the `PlaceImage`: @@ -1036,7 +1036,7 @@ export default function App() { const [isLarge, setIsLarge] = useState(false); const imageSize = isLarge ? 150 : 100; return ( -
- + ) } diff --git a/src/content/learn/react-compiler.md b/src/content/learn/react-compiler.md index 0ae499472..7c46673e7 100644 --- a/src/content/learn/react-compiler.md +++ b/src/content/learn/react-compiler.md @@ -311,7 +311,7 @@ export default defineConfig({ ### Webpack {/*usage-with-webpack*/} -A community Webpack loader is [now available here](https://github.com/SukkaW/react-compiler-webpack). +A community webpack loader is [now available here](https://github.com/SukkaW/react-compiler-webpack). ### Expo {/*usage-with-expo*/} diff --git a/src/content/learn/react-developer-tools.md b/src/content/learn/react-developer-tools.md index 5b141ea90..10d9e74f7 100644 --- a/src/content/learn/react-developer-tools.md +++ b/src/content/learn/react-developer-tools.md @@ -54,7 +54,11 @@ react-devtools ## 行動裝置（React Native） {/*mobile-react-native*/} +<<<<<<< HEAD 若要檢查使用 [React Native](https://reactnative.dev/) 建立的應用程式，你可以使用 [React Native DevTools](https://reactnative.dev/docs/react-native-devtools)，這是一個深度整合 React Developer Tools 的內建偵錯工具。所有功能都與瀏覽器擴充功能完全相同，包含原生元素的高亮顯示和選取功能。 +======= +To inspect apps built with [React Native](https://reactnative.dev/), you can use [React Native DevTools](https://reactnative.dev/docs/react-native-devtools), the built-in debugger that deeply integrates React Developer Tools. All features work identically to the browser extension, including native element highlighting and selection. +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff [深入了解 React Native 的偵錯功能。](https://reactnative.dev/docs/debugging) diff --git a/src/content/learn/render-and-commit.md b/src/content/learn/render-and-commit.md index ea772fc32..37e85307c 100644 --- a/src/content/learn/render-and-commit.md +++ b/src/content/learn/render-and-commit.md @@ -70,7 +70,7 @@ export default function Image() { 一但 component 被初始 render，你可以透過使用 [`set` 函式](/reference/react/useState#setstate) 更新其狀態來觸發之後的 render。更新 component 的狀態會自動加入重新 render 的 queue。(你可以將這個過程想像成一位餐廳顧客點完第一道菜後，根據他的口渴或飢餓程度，又繼續點了茶、點心或其他各種菜色的流程。) - + @@ -84,7 +84,11 @@ export default function Image() { 這段過程是遞迴的：如果更新的 component 回傳其他的 component，React 將會 render _那個_ component，如果 component 又回傳其他的 component，React 會接著 render _下一個_ component，以此類推。這個過程將一直持續到沒有回傳更多的 component，React 才知道應該在螢幕上顯示什麼。 +<<<<<<< HEAD 在接下來的範例，React 將會呼叫 `Gallery()` 和 `Image()` 幾次 +======= +In the following example, React will call `Gallery()` and `Image()` several times: +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff @@ -148,10 +152,17 @@ Rendering 必須永遠是一個[純運算](/learn/keeping-components-pure) ## 步驟 3：React 把更改 commit 到 DOM {/*step-3-react-commits-changes-to-the-dom*/} +<<<<<<< HEAD 在 rendering（呼叫）你的 component 後，React 將會更改你的 DOM。 * **對於初始 render，** React 會使用 [`appendChild()`](https://developer.mozilla.org/docs/Web/API/Node/appendChild) DOM API 在螢幕上顯示所有你建立的 DOM 節點。 * **對於重新 render，** React 會採取最小必要的操作 (在 rendering 時計算！)，以使得 DOM 與 rendering 後的的輸出相符。 +======= +After rendering (calling) your components, React will modify the DOM. + +* **For the initial render,** React will use the [`appendChild()`](https://developer.mozilla.org/docs/Web/API/Node/appendChild) DOM API to put all the DOM nodes it has created on screen. +* **For re-renders,** React will apply the minimal necessary operations (calculated while rendering!) to make the DOM match the latest rendering output. +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff **React 只有在 render 時有差異才會更改 DOM 節點。** 例如，這裡有一個 component，每秒從其 parent 傳遞不同的 props 重新 render。請注意，你可以在 `` 中輸入一些文字，更新它的 `value`，但是這些文字不會在 conponent 重新 render 時消失。 diff --git a/src/content/learn/setup.md b/src/content/learn/setup.md new file mode 100644 index 000000000..2c46ee148 --- /dev/null +++ b/src/content/learn/setup.md @@ -0,0 +1,28 @@ +--- +title: Setup +--- + + +React integrates with tools like editors, TypeScript, browser extensions, and compilers. This section will help you get your environment set up. + + + +## Editor Setup {/*editor-setup*/} + +See our [recommended editors](/learn/editor-setup) and learn how to set them up to work with React. + +## Using TypeScript {/*using-typescript*/} + +TypeScript is a popular way to add type definitions to JavaScript codebases. [Learn how to integrate TypeScript into your React projects](/learn/typescript). + +## React Developer Tools {/*react-developer-tools*/} + +React Developer Tools is a browser extension that can inspect React components, edit props and state, and identify performance problems. Learn how to install it [here](learn/react-developer-tools). + +## React Compiler {/*react-compiler*/} + +React Compiler is a tool that automatically optimizes your React app. [Learn more](/learn/react-compiler). + +## Next steps {/*next-steps*/} + +Head to the [Quick Start](/learn) guide for a tour of the most important React concepts you will encounter every day. diff --git a/src/content/learn/state-a-components-memory.md b/src/content/learn/state-a-components-memory.md index 75a1fd0b9..73d46bdab 100644 --- a/src/content/learn/state-a-components-memory.md +++ b/src/content/learn/state-a-components-memory.md @@ -1452,7 +1452,7 @@ If your linter is [configured for React](/learn/editor-setup#linting), you shoul #### Remove unnecessary state {/*remove-unnecessary-state*/} -When the button is clicked, this example should ask for the user's name and then display an alert greeting them. You tried to use state to keep the name, but for some reason it always shows "Hello, !". +When the button is clicked, this example should ask for the user's name and then display an alert greeting them. You tried to use state to keep the name, but for some reason the first time it shows "Hello, !", and then "Hello, [name]!" with the previous input every time after. To fix this code, remove the unnecessary state variable. (We will discuss about [why this didn't work](/learn/state-as-a-snapshot) later.) diff --git a/src/content/learn/tutorial-tic-tac-toe.md b/src/content/learn/tutorial-tic-tac-toe.md index 6487e8007..1c61d180a 100644 --- a/src/content/learn/tutorial-tic-tac-toe.md +++ b/src/content/learn/tutorial-tic-tac-toe.md @@ -295,7 +295,7 @@ export default function Square() { } ``` -The _browser_ section should be displaying a square with a X in it like this: +The _browser_ section should be displaying a square with an X in it like this: ![x-filled square](../images/tutorial/x-filled-square.png) @@ -1325,7 +1325,7 @@ Let's recap what happens when a user clicks the top left square on your board to 1. `handleClick` uses the argument (`0`) to update the first element of the `squares` array from `null` to `X`. 1. The `squares` state of the `Board` component was updated, so the `Board` and all of its children re-render. This causes the `value` prop of the `Square` component with index `0` to change from `null` to `X`. -In the end the user sees that the upper left square has changed from empty to having a `X` after clicking it. +In the end the user sees that the upper left square has changed from empty to having an `X` after clicking it. @@ -1406,7 +1406,7 @@ But wait, there's a problem. Try clicking on the same square multiple times: The `X` is overwritten by an `O`! While this would add a very interesting twist to the game, we're going to stick to the original rules for now. -When you mark a square with a `X` or an `O` you aren't first checking to see if the square already has a `X` or `O` value. You can fix this by *returning early*. You'll check to see if the square already has a `X` or an `O`. If the square is already filled, you will `return` in the `handleClick` function early--before it tries to update the board state. +When you mark a square with an `X` or an `O` you aren't first checking to see if the square already has an `X` or `O` value. You can fix this by *returning early*. You'll check to see if the square already has an `X` or an `O`. If the square is already filled, you will `return` in the `handleClick` function early--before it tries to update the board state. ```js {2,3,4} function handleClick(i) { @@ -1556,7 +1556,7 @@ It does not matter whether you define `calculateWinner` before or after the `Boa -You will call `calculateWinner(squares)` in the `Board` component's `handleClick` function to check if a player has won. You can perform this check at the same time you check if a user has clicked a square that already has a `X` or and `O`. We'd like to return early in both cases: +You will call `calculateWinner(squares)` in the `Board` component's `handleClick` function to check if a player has won. You can perform this check at the same time you check if a user has clicked a square that already has an `X` or an `O`. We'd like to return early in both cases: ```js {2} function handleClick(i) { diff --git a/src/content/reference/react-dom/client/createRoot.md b/src/content/reference/react-dom/client/createRoot.md index 54e7a7f1d..f71f8e9a3 100644 --- a/src/content/reference/react-dom/client/createRoot.md +++ b/src/content/reference/react-dom/client/createRoot.md @@ -344,10 +344,11 @@ export default function App({counter}) { It is uncommon to call `render` multiple times. Usually, your components will [update state](/reference/react/useState) instead. -### Show a dialog for uncaught errors {/*show-a-dialog-for-uncaught-errors*/} +### Error logging in production {/*error-logging-in-production*/} -By default, React will log all uncaught errors to the console. To implement your own error reporting, you can provide the optional `onUncaughtError` root option: +By default, React will log all errors to the console. To implement your own error reporting, you can provide the optional error handler root options `onUncaughtError`, `onCaughtError` and `onRecoverableError`: +<<<<<<< HEAD ```js [[1, 6, "onUncaughtError"], [2, 6, "error", 1], [3, 6, "errorInfo"], [4, 10, "componentStack"]] import { createRoot } from 'react-dom/client'; @@ -767,124 +768,35 @@ import { createRoot } from "react-dom/client"; import App from "./App.js"; import {reportCaughtError} from "./reportError"; import "./styles.css"; +======= +```js [[1, 6, "onCaughtError"], [2, 6, "error", 1], [3, 6, "errorInfo"], [4, 10, "componentStack", 15]] +import { createRoot } from "react-dom/client"; +import { reportCaughtError } from "./reportError"; +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff const container = document.getElementById("root"); const root = createRoot(container, { onCaughtError: (error, errorInfo) => { - if (error.message !== 'Known error') { + if (error.message !== "Known error") { reportCaughtError({ - error, + error, componentStack: errorInfo.componentStack, }); } - } -}); -root.render(); -``` - -```js src/App.js -import { useState } from 'react'; -import { ErrorBoundary } from "react-error-boundary"; - -export default function App() { - const [error, setError] = useState(null); - - function handleUnknown() { - setError("unknown"); - } - - function handleKnown() { - setError("known"); - } - - return ( - <> - { - setError(null); - }} - > - {error != null && } - This error will not show the error dialog: - - This error will show the error dialog: - - - - - ); -} - -function fallbackRender({ resetErrorBoundary }) { - return ( -
-

Error Boundary

-

Something went wrong.

- -
- ); -} - -function Throw({error}) { - if (error === "known") { - throw new Error('Known error') - } else { - foo.bar = 'baz'; - } -} -``` - -```json package.json hidden -{ - "dependencies": { - "react": "19.0.0-rc-3edc000d-20240926", - "react-dom": "19.0.0-rc-3edc000d-20240926", - "react-scripts": "^5.0.0", - "react-error-boundary": "4.0.3" }, - "main": "/index.js" -} -``` - - - -### Displaying a dialog for recoverable errors {/*displaying-a-dialog-for-recoverable-errors*/} - -React may automatically render a component a second time to attempt to recover from an error thrown in render. If successful, React will log a recoverable error to the console to notify the developer. To override this behavior, you can provide the optional `onRecoverableError` root option: - -```js [[1, 6, "onRecoverableError"], [2, 6, "error", 1], [3, 10, "error.cause"], [4, 6, "errorInfo"], [5, 11, "componentStack"]] -import { createRoot } from 'react-dom/client'; - -const root = createRoot( - document.getElementById('root'), - { - onRecoverableError: (error, errorInfo) => { - console.error( - 'Recoverable error', - error, - error.cause, - errorInfo.componentStack, - ); - } - } -); -root.render(); +}); ``` -The onRecoverableError option is a function called with two arguments: +The onCaughtError option is a function called with two arguments: -1. The error that React throws. Some errors may include the original cause as error.cause. -2. An errorInfo object that contains the componentStack of the error. +1. The error that was thrown. +2. An errorInfo object that contains the componentStack of the error. -You can use the `onRecoverableError` root option to display error dialogs: +Together with `onUncaughtError` and `onRecoverableError`, you can can implement your own error reporting system: +<<<<<<< HEAD ```html public/index.html hidden @@ -943,176 +855,99 @@ html, body { min-height: 300px; } opacity: 0.9; text-wrap: wrap; overflow: scroll; +======= +```js src/reportError.js +function reportError({ type, error, errorInfo }) { + // The specific implementation is up to you. + // `console.error()` is only used for demonstration purposes. + console.error(type, error, "Component Stack: "); + console.error("Component Stack: ", errorInfo.componentStack); +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff } -.text-red { - color: red; -} - -.-mb-20 { - margin-bottom: -20px; -} - -.mb-0 { - margin-bottom: 0; -} - -.mb-10 { - margin-bottom: 10px; -} - -pre { - text-wrap: wrap; -} - -pre.nowrap { - text-wrap: nowrap; -} - -.hidden { - display: none; -} -``` - -```js src/reportError.js hidden -function reportError({ title, error, componentStack, dismissable }) { - const errorDialog = document.getElementById("error-dialog"); - const errorTitle = document.getElementById("error-title"); - const errorMessage = document.getElementById("error-message"); - const errorBody = document.getElementById("error-body"); - const errorComponentStack = document.getElementById("error-component-stack"); - const errorStack = document.getElementById("error-stack"); - const errorClose = document.getElementById("error-close"); - const errorCause = document.getElementById("error-cause"); - const errorCauseMessage = document.getElementById("error-cause-message"); - const errorCauseStack = document.getElementById("error-cause-stack"); - const errorNotDismissible = document.getElementById("error-not-dismissible"); - - // Set the title - errorTitle.innerText = title; - - // Display error message and body - const [heading, body] = error.message.split(/\n(.*)/s); - errorMessage.innerText = heading; - if (body) { - errorBody.innerText = body; - } else { - errorBody.innerText = ''; - } - - // Display component stack - errorComponentStack.innerText = componentStack; - - // Display the call stack - // Since we already displayed the message, strip it, and the first Error: line. - errorStack.innerText = error.stack.replace(error.message, '').split(/\n(.*)/s)[1]; - - // Display the cause, if available - if (error.cause) { - errorCauseMessage.innerText = error.cause.message; - errorCauseStack.innerText = error.cause.stack; - errorCause.classList.remove('hidden'); - } else { - errorCause.classList.add('hidden'); - } - // Display the close button, if dismissible - if (dismissable) { - errorNotDismissible.classList.add('hidden'); - errorClose.classList.remove("hidden"); - } else { - errorNotDismissible.classList.remove('hidden'); - errorClose.classList.add("hidden"); +export function onCaughtErrorProd(error, errorInfo) { + if (error.message !== "Known error") { + reportError({ type: "Caught", error, errorInfo }); } - - // Show the dialog - errorDialog.classList.remove("hidden"); -} - -export function reportCaughtError({error, cause, componentStack}) { - reportError({ title: "Caught Error", error, componentStack, dismissable: true}); } -export function reportUncaughtError({error, cause, componentStack}) { - reportError({ title: "Uncaught Error", error, componentStack, dismissable: false }); +export function onUncaughtErrorProd(error, errorInfo) { + reportError({ type: "Uncaught", error, errorInfo }); } -export function reportRecoverableError({error, cause, componentStack}) { - reportError({ title: "Recoverable Error", error, componentStack, dismissable: true }); +export function onRecoverableErrorProd(error, errorInfo) { + reportError({ type: "Recoverable", error, errorInfo }); } ``` ```js src/index.js active import { createRoot } from "react-dom/client"; import App from "./App.js"; -import {reportRecoverableError} from "./reportError"; -import "./styles.css"; +import { + onCaughtErrorProd, + onRecoverableErrorProd, + onUncaughtErrorProd, +} from "./reportError"; const container = document.getElementById("root"); const root = createRoot(container, { - onRecoverableError: (error, errorInfo) => { - reportRecoverableError({ - error, - cause: error.cause, - componentStack: errorInfo.componentStack, - }); - } + // Keep in mind to remove these options in development to leverage + // React's default handlers or implement your own overlay for development. + // The handlers are only specfied unconditionally here for demonstration purposes. + onCaughtError: onCaughtErrorProd, + onRecoverableError: onRecoverableErrorProd, + onUncaughtError: onUncaughtErrorProd, }); root.render(); ``` ```js src/App.js -import { useState } from 'react'; -import { ErrorBoundary } from "react-error-boundary"; +import { Component, useState } from "react"; -// 🚩 Bug: Never do this. This will force an error. -let errorThrown = false; -export default function App() { - return ( - <> - - {!errorThrown && } -

This component threw an error, but recovered during a second render.

-

Since it recovered, no Error Boundary was shown, but onRecoverableError was used to show an error dialog.

- - - - ); +function Boom() { + foo.bar = "baz"; } -function fallbackRender() { - return ( -
-

Error Boundary

-

Something went wrong.

-
- ); -} +class ErrorBoundary extends Component { + state = { hasError: false }; -function Throw({error}) { - // Simulate an external value changing during concurrent render. - errorThrown = true; - foo.bar = 'baz'; + static getDerivedStateFromError(error) { + return { hasError: true }; + } + + render() { + if (this.state.hasError) { + return

Something went wrong.

; + } + return this.props.children; + } } -``` -```json package.json hidden -{ - "dependencies": { - "react": "19.0.0-rc-3edc000d-20240926", - "react-dom": "19.0.0-rc-3edc000d-20240926", - "react-scripts": "^5.0.0", - "react-error-boundary": "4.0.3" - }, - "main": "/index.js" +export default function App() { + const [triggerUncaughtError, settriggerUncaughtError] = useState(false); + const [triggerCaughtError, setTriggerCaughtError] = useState(false); + + return ( + <> + + {triggerUncaughtError && } + + {triggerCaughtError && ( + + + + )} + + ); } ``` - ---- ## Troubleshooting {/*troubleshooting*/} ### I've created a root, but nothing is displayed {/*ive-created-a-root-but-nothing-is-displayed*/} diff --git a/src/content/reference/react-dom/client/hydrateRoot.md b/src/content/reference/react-dom/client/hydrateRoot.md index b1eeca30c..19c6c313a 100644 --- a/src/content/reference/react-dom/client/hydrateRoot.md +++ b/src/content/reference/react-dom/client/hydrateRoot.md @@ -99,7 +99,7 @@ An app fully built with React will usually not have any calls to `root.unmount`. This is mostly useful if your React root's DOM node (or any of its ancestors) may get removed from the DOM by some other code. For example, imagine a jQuery tab panel that removes inactive tabs from the DOM. If a tab gets removed, everything inside it (including the React roots inside) would get removed from the DOM as well. You need to tell React to "stop" managing the removed root's content by calling `root.unmount`. Otherwise, the components inside the removed root won't clean up and free up resources like subscriptions. -Calling `root.unmount` will unmount all the components in the root and "detach" React from the root DOM node, including removing any event handlers or state in the tree. +Calling `root.unmount` will unmount all the components in the root and "detach" React from the root DOM node, including removing any event handlers or state in the tree. #### Parameters {/*root-unmount-parameters*/} @@ -270,7 +270,7 @@ export default function App() { -This only works one level deep, and is intended to be an escape hatch. Don’t overuse it. Unless it’s text content, React still won’t attempt to patch it up, so it may remain inconsistent until future updates. +This only works one level deep, and is intended to be an escape hatch. Don’t overuse it. React will **not** attempt to patch mismatched text content. --- @@ -374,10 +374,11 @@ export default function App({counter}) { It is uncommon to call [`root.render`](#root-render) on a hydrated root. Usually, you'll [update state](/reference/react/useState) inside one of the components instead. -### Show a dialog for uncaught errors {/*show-a-dialog-for-uncaught-errors*/} +### Error logging in production {/*error-logging-in-production*/} -By default, React will log all uncaught errors to the console. To implement your own error reporting, you can provide the optional `onUncaughtError` root option: +By default, React will log all errors to the console. To implement your own error reporting, you can provide the optional error handler root options `onUncaughtError`, `onCaughtError` and `onRecoverableError`: +<<<<<<< HEAD ```js [[1, 7, "onUncaughtError"], [2, 7, "error", 1], [3, 7, "errorInfo"], [4, 11, "componentStack"]] import { hydrateRoot } from 'react-dom/client'; @@ -566,81 +567,35 @@ export function reportRecoverableError({error, cause, componentStack}) { ``` ```js src/index.js active +======= +```js [[1, 6, "onCaughtError"], [2, 6, "error", 1], [3, 6, "errorInfo"], [4, 10, "componentStack", 15]] +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff import { hydrateRoot } from "react-dom/client"; -import App from "./App.js"; -import {reportUncaughtError} from "./reportError"; -import "./styles.css"; -import {renderToString} from 'react-dom/server'; +import { reportCaughtError } from "./reportError"; const container = document.getElementById("root"); -const root = hydrateRoot(container, , { - onUncaughtError: (error, errorInfo) => { - if (error.message !== 'Known error') { - reportUncaughtError({ +const root = hydrateRoot(container, { + onCaughtError: (error, errorInfo) => { + if (error.message !== "Known error") { + reportCaughtError({ error, - componentStack: errorInfo.componentStack + componentStack: errorInfo.componentStack, }); } - } + }, }); ``` -```js src/App.js -import { useState } from 'react'; - -export default function App() { - const [throwError, setThrowError] = useState(false); - - if (throwError) { - foo.bar = 'baz'; - } - - return ( -
- This error shows the error dialog: - -
- ); -} -``` - - - - -### Displaying Error Boundary errors {/*displaying-error-boundary-errors*/} - -By default, React will log all errors caught by an Error Boundary to `console.error`. To override this behavior, you can provide the optional `onCaughtError` root option for errors caught by an [Error Boundary](/reference/react/Component#catching-rendering-errors-with-an-error-boundary): - -```js [[1, 7, "onCaughtError"], [2, 7, "error", 1], [3, 7, "errorInfo"], [4, 11, "componentStack"]] -import { hydrateRoot } from 'react-dom/client'; - -const root = hydrateRoot( - document.getElementById('root'), - , - { - onCaughtError: (error, errorInfo) => { - console.error( - 'Caught error', - error, - errorInfo.componentStack - ); - } - } -); -root.render(); -``` - The onCaughtError option is a function called with two arguments: -1. The error that was caught by the boundary. +1. The error that was thrown. 2. An errorInfo object that contains the componentStack of the error. -You can use the `onCaughtError` root option to display error dialogs or filter known errors from logging: +Together with `onUncaughtError` and `onRecoverableError`, you can implement your own error reporting system: +<<<<<<< HEAD ```html public/index.html hidden @@ -702,180 +657,97 @@ html, body { min-height: 300px; } opacity: 0.9; text-wrap: wrap; overflow: scroll; -} - -.text-red { - color: red; -} - -.-mb-20 { - margin-bottom: -20px; -} - -.mb-0 { - margin-bottom: 0; -} - -.mb-10 { - margin-bottom: 10px; -} - -pre { - text-wrap: wrap; -} - -pre.nowrap { - text-wrap: nowrap; -} - -.hidden { - display: none; -} -``` - -```js src/reportError.js hidden -function reportError({ title, error, componentStack, dismissable }) { - const errorDialog = document.getElementById("error-dialog"); - const errorTitle = document.getElementById("error-title"); - const errorMessage = document.getElementById("error-message"); - const errorBody = document.getElementById("error-body"); - const errorComponentStack = document.getElementById("error-component-stack"); - const errorStack = document.getElementById("error-stack"); - const errorClose = document.getElementById("error-close"); - const errorCause = document.getElementById("error-cause"); - const errorCauseMessage = document.getElementById("error-cause-message"); - const errorCauseStack = document.getElementById("error-cause-stack"); - const errorNotDismissible = document.getElementById("error-not-dismissible"); - - // Set the title - errorTitle.innerText = title; - - // Display error message and body - const [heading, body] = error.message.split(/\n(.*)/s); - errorMessage.innerText = heading; - if (body) { - errorBody.innerText = body; - } else { - errorBody.innerText = ''; - } - - // Display component stack - errorComponentStack.innerText = componentStack; - - // Display the call stack - // Since we already displayed the message, strip it, and the first Error: line. - errorStack.innerText = error.stack.replace(error.message, '').split(/\n(.*)/s)[1]; - - // Display the cause, if available - if (error.cause) { - errorCauseMessage.innerText = error.cause.message; - errorCauseStack.innerText = error.cause.stack; - errorCause.classList.remove('hidden'); - } else { - errorCause.classList.add('hidden'); - } - // Display the close button, if dismissible - if (dismissable) { - errorNotDismissible.classList.add('hidden'); - errorClose.classList.remove("hidden"); - } else { - errorNotDismissible.classList.remove('hidden'); - errorClose.classList.add("hidden"); +======= +```js src/reportError.js +function reportError({ type, error, errorInfo }) { + // The specific implementation is up to you. + // `console.error()` is only used for demonstration purposes. + console.error(type, error, "Component Stack: "); + console.error("Component Stack: ", errorInfo.componentStack); +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff +} + +export function onCaughtErrorProd(error, errorInfo) { + if (error.message !== "Known error") { + reportError({ type: "Caught", error, errorInfo }); } - - // Show the dialog - errorDialog.classList.remove("hidden"); } -export function reportCaughtError({error, cause, componentStack}) { - reportError({ title: "Caught Error", error, componentStack, dismissable: true}); +export function onUncaughtErrorProd(error, errorInfo) { + reportError({ type: "Uncaught", error, errorInfo }); } -export function reportUncaughtError({error, cause, componentStack}) { - reportError({ title: "Uncaught Error", error, componentStack, dismissable: false }); -} - -export function reportRecoverableError({error, cause, componentStack}) { - reportError({ title: "Recoverable Error", error, componentStack, dismissable: true }); +export function onRecoverableErrorProd(error, errorInfo) { + reportError({ type: "Recoverable", error, errorInfo }); } ``` ```js src/index.js active import { hydrateRoot } from "react-dom/client"; import App from "./App.js"; -import {reportCaughtError} from "./reportError"; -import "./styles.css"; +import { + onCaughtErrorProd, + onRecoverableErrorProd, + onUncaughtErrorProd, +} from "./reportError"; const container = document.getElementById("root"); -const root = hydrateRoot(container, , { - onCaughtError: (error, errorInfo) => { - if (error.message !== 'Known error') { - reportCaughtError({ - error, - componentStack: errorInfo.componentStack - }); - } - } +hydrateRoot(container, , { + // Keep in mind to remove these options in development to leverage + // React's default handlers or implement your own overlay for development. + // The handlers are only specfied unconditionally here for demonstration purposes. + onCaughtError: onCaughtErrorProd, + onRecoverableError: onRecoverableErrorProd, + onUncaughtError: onUncaughtErrorProd, }); ``` ```js src/App.js -import { useState } from 'react'; -import { ErrorBoundary } from "react-error-boundary"; +import { Component, useState } from "react"; -export default function App() { - const [error, setError] = useState(null); - - function handleUnknown() { - setError("unknown"); +function Boom() { + foo.bar = "baz"; +} + +class ErrorBoundary extends Component { + state = { hasError: false }; + + static getDerivedStateFromError(error) { + return { hasError: true }; } - function handleKnown() { - setError("known"); + render() { + if (this.state.hasError) { + return

Something went wrong.

; + } + return this.props.children; } - - return ( - <> - { - setError(null); - }} - > - {error != null && } - This error will not show the error dialog: - - This error will show the error dialog: - - - - - ); } -function fallbackRender({ resetErrorBoundary }) { +export default function App() { + const [triggerUncaughtError, settriggerUncaughtError] = useState(false); + const [triggerCaughtError, setTriggerCaughtError] = useState(false); + return ( -
-

Error Boundary

-

Something went wrong.

- -
+ <> + + {triggerUncaughtError && } + + {triggerCaughtError && ( + + + + )} + ); } - -function Throw({error}) { - if (error === "known") { - throw new Error('Known error') - } else { - foo.bar = 'baz'; - } -} ``` +<<<<<<< HEAD ```json package.json hidden { "dependencies": { @@ -922,6 +794,8 @@ You can use the `onRecoverableError` root option to display error dialogs for hy +======= +>>>>>>> ab18d2f0f5151ab0c927a12eb0a64f8170762eff ```html public/index.html hidden @@ -930,226 +804,12 @@ You can use the `onRecoverableError` root option to display error dialogs for hy - - -
Server
+
Server content before hydration.
``` - -```css src/styles.css active -label, button { display: block; margin-bottom: 20px; } -html, body { min-height: 300px; } - -#error-dialog { - position: absolute; - top: 0; - right: 0; - bottom: 0; - left: 0; - background-color: white; - padding: 15px; - opacity: 0.9; - text-wrap: wrap; - overflow: scroll; -} - -.text-red { - color: red; -} - -.-mb-20 { - margin-bottom: -20px; -} - -.mb-0 { - margin-bottom: 0; -} - -.mb-10 { - margin-bottom: 10px; -} - -pre { - text-wrap: wrap; -} - -pre.nowrap { - text-wrap: nowrap; -} - -.hidden { - display: none; -} -``` - -```js src/reportError.js hidden -function reportError({ title, error, componentStack, dismissable }) { - const errorDialog = document.getElementById("error-dialog"); - const errorTitle = document.getElementById("error-title"); - const errorMessage = document.getElementById("error-message"); - const errorBody = document.getElementById("error-body"); - const errorComponentStack = document.getElementById("error-component-stack"); - const errorStack = document.getElementById("error-stack"); - const errorClose = document.getElementById("error-close"); - const errorCause = document.getElementById("error-cause"); - const errorCauseMessage = document.getElementById("error-cause-message"); - const errorCauseStack = document.getElementById("error-cause-stack"); - const errorNotDismissible = document.getElementById("error-not-dismissible"); - - // Set the title - errorTitle.innerText = title; - - // Display error message and body - const [heading, body] = error.message.split(/\n(.*)/s); - errorMessage.innerText = heading; - if (body) { - errorBody.innerText = body; - } else { - errorBody.innerText = ''; - } - - // Display component stack - errorComponentStack.innerText = componentStack; - - // Display the call stack - // Since we already displayed the message, strip it, and the first Error: line. - errorStack.innerText = error.stack.replace(error.message, '').split(/\n(.*)/s)[1]; - - // Display the cause, if available - if (error.cause) { - errorCauseMessage.innerText = error.cause.message; - errorCauseStack.innerText = error.cause.stack; - errorCause.classList.remove('hidden'); - } else { - errorCause.classList.add('hidden'); - } - // Display the close button, if dismissible - if (dismissable) { - errorNotDismissible.classList.add('hidden'); - errorClose.classList.remove("hidden"); - } else { - errorNotDismissible.classList.remove('hidden'); - errorClose.classList.add("hidden"); - } - - // Show the dialog - errorDialog.classList.remove("hidden"); -} - -export function reportCaughtError({error, cause, componentStack}) { - reportError({ title: "Caught Error", error, componentStack, dismissable: true}); -} - -export function reportUncaughtError({error, cause, componentStack}) { - reportError({ title: "Uncaught Error", error, componentStack, dismissable: false }); -} - -export function reportRecoverableError({error, cause, componentStack}) { - reportError({ title: "Recoverable Error", error, componentStack, dismissable: true }); -} -``` - -```js src/index.js active -import { hydrateRoot } from "react-dom/client"; -import App from "./App.js"; -import {reportRecoverableError} from "./reportError"; -import "./styles.css"; - -const container = document.getElementById("root"); -const root = hydrateRoot(container, , { - onRecoverableError: (error, errorInfo) => { - reportRecoverableError({ - error, - cause: error.cause, - componentStack: errorInfo.componentStack - }); - } -}); -``` - -```js src/App.js -import { useState } from 'react'; -import { ErrorBoundary } from "react-error-boundary"; - -export default function App() { - const [error, setError] = useState(null); - - function handleUnknown() { - setError("unknown"); - } - - function handleKnown() { - setError("known"); - } - - return ( - {typeof window !== 'undefined' ? 'Client' : 'Server'} - ); -} - -function fallbackRender({ resetErrorBoundary }) { - return ( -
-

Error Boundary

-

Something went wrong.

- -
- ); -} - -function Throw({error}) { - if (error === "known") { - throw new Error('Known error') - } else { - foo.bar = 'baz'; - } -} -``` - -```json package.json hidden -{ - "dependencies": { - "react": "19.0.0-rc-3edc000d-20240926", - "react-dom": "19.0.0-rc-3edc000d-20240926", - "react-scripts": "^5.0.0", - "react-error-boundary": "4.0.3" - }, - "main": "/index.js" -} -``` - ## Troubleshooting {/*troubleshooting*/} diff --git a/src/content/reference/react-dom/components/form.md b/src/content/reference/react-dom/components/form.md index b3c849e72..115e6a4cd 100644 --- a/src/content/reference/react-dom/components/form.md +++ b/src/content/reference/react-dom/components/form.md @@ -214,7 +214,7 @@ export default function App() { ]); async function sendMessage(formData) { const sentMessage = await deliverMessage(formData.get("message")); - setMessages([...messages, { text: sentMessage }]); + setMessages((messages) => [...messages, { text: sentMessage }]); } return ; } diff --git a/src/content/reference/react-dom/components/input.md b/src/content/reference/react-dom/components/input.md index 08672e836..42caf2edc 100644 --- a/src/content/reference/react-dom/components/input.md +++ b/src/content/reference/react-dom/components/input.md @@ -297,7 +297,7 @@ Give a `name` to every ``, for example ` -By default, *any* `