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                        课程
                    
                        /前端开发
                        
                            /Html5
                        
                        /炫丽的倒计时效果Canvas绘图与动画基础

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html;charset=UTF-8">
<title>Document</title>
</head>
<body>
<canvas id="canvas" style="border:1px solid #777;margin:50px auto;display:block;" ></canvas>
<script>
var tangram=[
{p[{x:0,y:0},{x:300,y:300},{x:600,y:0}],color:"#777"},
{p[{x:0,y:0},{x:300,y:300},{x:0,y:600}],color:"blue"},
{p[{x:0,y:600},{x:150,y:450},{x:300,y:600}],color:"black"},
{p[{x:150,y:450},{x:300,y:600},{x:450,y:450},{x:300,y:300}],color:"yellow"},
{p[{x:450,y:450},{x:300,y:300},{x:450,y:150}],color:"green"},
{p[{x:450,y:450},{x:450,y:150},{x:600,y:0},{x:600,y:300}],color:"pink"},
{p[{x:600,y:300},{x:600,y:600},{x:300,y:600}],color:"grey"}
];

window.onload=function(){
var canvas=document.getElementById("canvas");
canvas.width=800;
canvas.height=800;
var context=canvas.getContext("2d");
for (var i = 0; i < tangram.length; i++) {
draw(tangram[i],context);
};
}

function draw(piece,cxt){
cxt.beginPath();
cxt.moveTo(piece.p[0].x,piece.p[0].y);
for (var i = 1; i < piece.p.length; i++) {
cxt.lineTo(piece.p[i].x,piece.p[i].y);
};

cxt.closePath();
cxt.fillStyle=piece.color;
cxt.fill();
}
</script>
</body>
</html>

七巧板写不出来，canvas内总是空白一片，好忧伤啊