<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>绘制径向渐变</title>
<script>
function draw(id){
var canvas=document.getElementById(id);
if(canvas==null)
{
return false;
}
var context=canvas.getContext("2d");
//createRadiaGradient径向渐变
var g1=context.createRadiaGradient(400,0,0,400,0,400);
g1.addColorStop(0.1,"rgb(255,255,0)");
g1.addColorStop(0.3,"rgb(255,0,255)");
g1.addColorStop(1,"rgb(0,255,255)");
content.fillStyle=g1;
context.fillRect(0,0,500,500);
context.closePath();
context.fill();
context.stroken();
}
</script>
</head>
<body onload="draw("canvas");">
<canvas id="canvas" width="500" height="500"></canvas>
</body>
</html>