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committedMar 18, 2025
New sample
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‎DynamicQuery/BlogPost.cs

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public record BlogPost
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{
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public required int Id { get; set; }
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public required string Title { get; set; }
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public required string Content { get; set; }
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public required string Author { get; set; }
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public required DateTime Created { get; set; }
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public required DateTime Updated { get; set; }
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public required List<string> Tags { get; set; }
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}

‎DynamicQuery/BloggingContext.cs

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using Microsoft.EntityFrameworkCore;
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public class BloggingContext : DbContext
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{
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public DbSet<BlogPost> BlogPosts { get; set; } = default!;
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protected override void OnConfiguring(DbContextOptionsBuilder options)
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=> options.UseSqlite("DataSource=myshareddb;mode=memory;cache=shared");
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protected override void OnModelCreating(ModelBuilder modelBuilder)
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{
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modelBuilder.ApplyConfiguration(new BlogPostTypeConfiguration());
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}
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}

‎DynamicQuery/DynamicQuery.csproj

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<Project Sdk="Microsoft.NET.Sdk">
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<PropertyGroup>
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<OutputType>Exe</OutputType>
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<TargetFramework>net8.0</TargetFramework>
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<LangVersion>preview</LangVersion>
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<ImplicitUsings>enable</ImplicitUsings>
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<Nullable>enable</Nullable>
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</PropertyGroup>
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<ItemGroup>
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<PackageReference Include="Microsoft.EntityFrameworkCore.Sqlite" Version="9.0.3" />
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<PackageReference Include="System.Linq.Dynamic.Core" Version="1.6.0.2" />
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</ItemGroup>
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</Project>

‎DynamicQuery/DynamicQuery.sln

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Microsoft Visual Studio Solution File, Format Version 12.00
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Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DynamicQuery", "DynamicQuery.csproj", "{CDAC80B9-217D-411D-97D5-94193BF1AB70}"
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EndProject
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Global
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GlobalSection(SolutionConfigurationPlatforms) = preSolution
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Debug|Any CPU = Debug|Any CPU
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Release|Any CPU = Release|Any CPU
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EndGlobalSection
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GlobalSection(ProjectConfigurationPlatforms) = postSolution
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{CDAC80B9-217D-411D-97D5-94193BF1AB70}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
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{CDAC80B9-217D-411D-97D5-94193BF1AB70}.Debug|Any CPU.Build.0 = Debug|Any CPU
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{CDAC80B9-217D-411D-97D5-94193BF1AB70}.Release|Any CPU.ActiveCfg = Release|Any CPU
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{CDAC80B9-217D-411D-97D5-94193BF1AB70}.Release|Any CPU.Build.0 = Release|Any CPU
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EndGlobalSection
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EndGlobal

‎DynamicQuery/Program.cs

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using System.Linq.Expressions;
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using System.Linq.Dynamic.Core;
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using Microsoft.EntityFrameworkCore;
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using Microsoft.EntityFrameworkCore.Metadata.Builders;
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using var dbContext = new BloggingContext();
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dbContext.Database.EnsureCreated();
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Console.WriteLine("What column would you like to return?");
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var column = Console.ReadLine();
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var columnSelector = GenerateColumnSelector(column).Compile();
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var query = dbContext.BlogPosts.Select(s => new ReturnColumn
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{
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Id = s.Id,
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Column = columnSelector.Invoke(s)
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});
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var queryString = query.ToQueryString();
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Console.WriteLine(queryString);
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var queryWithDynamic = dbContext
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.BlogPosts
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.Select<ReturnColumn>($"new(Id, {column} AS Column)");
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var queryStringWithDynamic = queryWithDynamic.ToQueryString();
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Console.WriteLine(queryStringWithDynamic);
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Expression<Func<BlogPost, string>> GenerateColumnSelector(string? column)
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{
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return column switch
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{
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"Title" => s => s.Title,
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"Content" => s => s.Content,
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"Author" => s => s.Author,
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_ => throw new ArgumentException("Invalid column name")
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};
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}
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public class ReturnColumn
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{
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public int Id { get; set; }
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public string Column { get; set; }
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}
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public class BlogPostTypeConfiguration : IEntityTypeConfiguration<BlogPost>
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{
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public void Configure(EntityTypeBuilder<BlogPost> builder)
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{
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builder.HasKey(x => x.Id);
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builder.Property(x => x.Title).HasMaxLength(2048).IsRequired();
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builder.Property(x => x.Content).IsRequired();
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builder.Property(x => x.Author).HasMaxLength(2048).IsRequired();
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builder.Property(x => x.Created).IsRequired();
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builder.Property(x => x.Updated).IsRequired();
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builder.Property(x => x.Tags).IsRequired();
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}
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}

‎DynamicQuery/README.md

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# Solving Problems you wouldn't have if you wouldn't use Entity Framework
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Long title - short intro? Well - I recently came across my own stupidity and wanted to display that to the world. Basically, how to dynamically selecting a column with Entity Framework.
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Found [here](https://steven-giesel.com/blogPost/1b432667-3b2d-4c41-8557-b4c3a3c554d9/solving-problems-you-wouldnt-have-if-you-wouldnt-use-entity-framework)

‎PerformanceNet10/PerformanceNet10.sln

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Microsoft Visual Studio Solution File, Format Version 12.00
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Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "PerformanceNet10", "PerformanceNet10\PerformanceNet10.csproj", "{D8EAFDC8-5C18-4384-8FF4-51A1455C4725}"
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EndProject
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Global
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GlobalSection(SolutionConfigurationPlatforms) = preSolution
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Debug|Any CPU = Debug|Any CPU
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Release|Any CPU = Release|Any CPU
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EndGlobalSection
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GlobalSection(ProjectConfigurationPlatforms) = postSolution
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{D8EAFDC8-5C18-4384-8FF4-51A1455C4725}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
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{D8EAFDC8-5C18-4384-8FF4-51A1455C4725}.Debug|Any CPU.Build.0 = Debug|Any CPU
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{D8EAFDC8-5C18-4384-8FF4-51A1455C4725}.Release|Any CPU.ActiveCfg = Release|Any CPU
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{D8EAFDC8-5C18-4384-8FF4-51A1455C4725}.Release|Any CPU.Build.0 = Release|Any CPU
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EndGlobalSection
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EndGlobal

‎PerformanceNet10/PerformanceNet10/PerformanceNet10.csproj

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<Project Sdk="Microsoft.NET.Sdk">
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<PropertyGroup>
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<OutputType>Exe</OutputType>
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<TargetFrameworks>net9.0;net10.0</TargetFrameworks>
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<ImplicitUsings>enable</ImplicitUsings>
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<Nullable>enable</Nullable>
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</PropertyGroup>
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<ItemGroup>
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<PackageReference Include="BenchmarkDotNet" Version="0.14.1-nightly.20250107.205" />
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</ItemGroup>
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</Project>

‎PerformanceNet10/PerformanceNet10/Program.cs

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using BenchmarkDotNet.Attributes;
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using BenchmarkDotNet.Jobs;
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using BenchmarkDotNet.Running;
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BenchmarkSwitcher.FromAssembly(typeof(VirtualizationAndInlineBenchmarks).Assembly).Run();
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[SimpleJob(RuntimeMoniker.Net90, baseline: true)]
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[SimpleJob(RuntimeMoniker.Net10_0)]
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[MemoryDiagnoser]
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public class VirtualizationAndInlineBenchmarks
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{
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private static readonly List<int> Numbers = Enumerable.Range(0, 10000).Select(s => Random.Shared.Next()).ToList();
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// See: https://learn.microsoft.com/en-us/dotnet/core/whats-new/dotnet-10/runtime
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[Benchmark]
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public int Sum()
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{
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var sum = 0;
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IEnumerable<int> temp = Numbers;
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foreach (var t in temp)
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sum += t;
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return sum;
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}
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// See: https://learn.microsoft.com/en-us/dotnet/core/whats-new/dotnet-10/runtime
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[Benchmark]
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public int StackallocOfArrays()
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{
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int[] numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11];
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var sum = 0;
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for (var i = 0; i < numbers.Length; i++)
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sum += numbers[i];
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return sum;
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}
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}
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[SimpleJob(RuntimeMoniker.Net90, baseline: true)]
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[SimpleJob(RuntimeMoniker.Net10_0)]
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[MemoryDiagnoser]
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public class CommonListOperationBenchmarks
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{
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[Benchmark]
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public List<int> ListAdd10000()
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{
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var list = new List<int>();
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for (var i = 0; i < 10_000; i++)
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{
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list.Add(i);
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}
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return list;
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}
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[Benchmark]
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public List<int> ListAdd10000PreAlloc()
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{
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var list = new List<int>(10_000);
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for (var i = 0; i < 10_000; i++)
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{
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list.Add(i);
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}
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return list;
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}
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}

‎README.md

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| BlogPost | Publish Date |
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| -------------------------------------------------------------------------------------------------------------- | ------------ |
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| [Solving Problems you wouldn't have if you wouldn't use Entity Framework](DynamicQuery/) | 24.04.2025 |
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| [Tailwind v4 with Blazor - It just got easier](BlazorTailwind4/) | 03.03.2025 |
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| [ToArray(Async) vs ToList(Async) in Entity Framework 8](BenchmarkToArrayToListEF/) | 28.10.2024 |
910
| [How to test HttpClient inside API Tests](FakeHttpClient/) | 02.09.2024 |

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