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<!DOCTYPE html>
<head>
<meta charset=utf-8 />
<title>canvas</title>
<script type='text/javascript'>
window.onload = function(){
getCanvas();
};
//canvase»æͼ
function getCanvas(){
//»ñµÃcanvasÔªËؼ°Æä»æͼÉÏÏÂÎÄ
var canvas = document.getElementById('canvasId');
var »ªÓîƽ̨ context = canvas.getContext('2d');
//Óþø¶Ô·±êÀ´´´½¨Ò»Ìõ·¾¶
context.beginPath();
context.moveTo(0,200);
context.lineTo(200,0);
//½«ÕâÌõÏÈ»æÖƵ½canvasÉÏ
context.stroke();
}
</script>
</head>
<body>
<canvas id='canvasId' width="200px" height='200px' »ªÓîƽ̨ style='width:400px;height:200px;' ></canvas>
</body>
</html>
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