<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title></title>
<style>
body {
margin:0px;
padding:0px;
}
#aa{
border:1px solid blanchedalmond;
background-color:blue;
}
</style>
<script>
window.onload =function(){
var canvas=document.getElementById("aa");
var context =canvas.getContext ("2d");
context.beginPath();
context.moveTo (200,canvas.height/2)
context.lineTo (canvas.width-200,canvas.height /2);
context.lineWidth =20;
context.strokeStyle ="#ff00000";
context.lineCap ="round";
context.stroke ();
context.beginPath();
context.moveTo (200,canvas.height/2+50)
context.lineTo (canvas.width-200,canvas.height /2);
context.lineWidth =20;
context.strokeStyle ="#ff00000";
context.lineCap ="square";
context.stroke ();
};
</script>
</head>
<body>
<canvas id="aa" width="578" height="200">
</canvas>
</body>
</html>
与其放在电脑里占内存，还不如拿出来帮助一群小白白之html篇之三
原文：http://www.cnblogs.com/mikou2017/p/6883219.html