-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathpen.html
71 lines (70 loc) · 1.93 KB
/
pen.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>drawing</title>
<style>
canvas{
border: 1px solid black;
}
span{
cursor:pointer;
}
</style>
</head>
<body>
<canvas height="600" width="1100"></canvas>
<span onclick="pen()">🖊</span>
<span onclick="er()">橡皮</span>
<span onclick="bolder()">加粗</span>
<span onclick="col()">红色</span>
<span></span>
<script>
var c = document.getElementsByTagName('canvas')[0];
var ctx = c.getContext('2d');
var gj = '',
size = 10,
color = 'black';
var pen = function(){
gj = 'pen';
}
var er = function(){
gj = 'er';
}
var bolder = function(){
size += 10;
}
var col = function(){
color = 'red'
}
c.onmousedown = function(ev){
switch (gj) {
case 'pen':
ctx.beginPath();
ctx.strokeStyle = color;
ctx.lineCap = 'round'
ctx.lineWidth = size;
ctx.moveTo(ev.clientX,ev.clientY);
c.onmousemove = function(ev){
ctx.lineTo(ev.clientX,ev.clientY);
ctx.stroke();
}
break;
case 'er':
ctx.beginPath();
ctx.strokeStyle = 'white';
ctx.lineWidth = size;
ctx.moveTo(ev.clientX,ev.clientY);
c.onmousemove = function(ev){
ctx.lineTo(ev.clientX,ev.clientY);
ctx.stroke();
}
break;
}
}
c.onmouseup = c.onmouseleave = function(){
c.onmousemove = null;
}
</script>
</body>
</html>