html5 canvas贝塞尔曲线篇(上)

<!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">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>html5 canvas贝塞尔曲线篇</title>
<script src="js/modernizr.js"></script>
</head>
 
<body>
<h1>html5 canvas贝塞尔曲线篇</h1>
 
<script type="text/javascript">
window.addEventListener('load',eventWindowLoaded,false);
function eventWindowLoaded(){
    canvasApp();
}
function canvasSupport(){
    return Modernizr.canvas;
}
function canvasApp(){
    if(!canvasSupport()){
        return;
    }else{
        var theCanvas = document.getElementById('canvas')
        var context = theCanvas.getContext("2d")
 
    }
    drawScreen();
    function drawScreen(){
        //颜色粉色，线宽10,
         context.beginPath();
         context.strokeStyle="red";
             context.lineWidth=2;
         context.moveTo(0,0);  //从0,0开始
          
         //context.quadraticCurveTo(cpx,cpy,x,y);
          
         context.quadraticCurveTo(200,50,0,100);  //0,100结束，创建弧线的点位于（200,25）
         context.stroke();
         context.closePath();
          
    }
}
 
 
</script>
<canvas id="canvas" width="500" height="500">
你的浏览器无法使用canvas
如有疑问加QQ：1035417613;小白童鞋；你的支持是我最大的快乐！！
</canvas>
</body>
</html>