-
Notifications
You must be signed in to change notification settings - Fork 3
/
Copy pathdemo09.html
57 lines (44 loc) · 1.05 KB
/
demo09.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
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>canvas 鼠标画笔 </title>
</head>
<body>
<canvas id="myCanvas" style="border:1px solid #ddd;display:block;margin:20px auto;"></canvas>
<script>
var myCanvas=document.getElementById("myCanvas");
myCanvas.width="500";
myCanvas.height="300";
var cxt=myCanvas.getContext("2d");
var canvaL=myCanvas.offsetLeft;
var canvaT=myCanvas.offsetTop;
myCanvas.onmousedown=function(e){
var ev=e||window.event;
var left=ev.clientX;
var top=ev.clientY;
var x=left-canvaL;
var y=top-canvaT;
cxt.moveTo(x,y);
myCanvas.onmousemove=function(e){
var ev=e||window.event;
var left=ev.clientX;
var top=ev.clientY;
var x=left-canvaL;
var y=top-canvaT;
cxt.lineTo(x,y);
cxt.stroke();
}
myCanvas.onmouseup=function(){
myCanvas.onmouseup=null;
myCanvas.onmousemove=null;
}
myCanvas.onmouseout=function(){
myCanvas.onmouseup=null;
myCanvas.onmousemove=null;
myCanvas.onmouseout=null;
}
}
</script>
</body>
</html>