​x
 
<!DOCTYPE html>
<html>
<body>
​
<canvas id="myCanvas" width="300" height="150" style="border:1px solid #d3d3d3;">
Your browser does not support the HTML5 canvas tag.
</canvas>
​
<script>
var c=document.getElementById("myCanvas");
var ctx=c.getContext("2d");
ctx.fillStyle="green";
ctx.fillRect(10,10,50,50);
​
function copy()
{
var imgData=ctx.getImageData(10,10,50,50);
ctx.putImageData(imgData,10,70);
}
</script>
​
<button onclick="copy()">复制</button>
​
</body>
</html>
​