<?xml version="1.0" encoding="utf-8"?>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Canvas drag and drop: helper file</title>
<script type="application/ecmascript">
function paint(color)
	{var canvas = document.querySelector('canvas'),
	c = canvas.getContext('2d');
	c.fillStyle = color;
	c.beginPath();
	c.moveTo(0,0);
	c.lineTo(100,0);
	c.lineTo(100,100);
	c.lineTo(0,100);
	c.closePath();
	c.fill();}
function start(event)
	{event.dataTransfer.effectAllowed = 'copy';
	event.dataTransfer.setData('text/plain', 'green');}
</script>
</head>
<body onload="paint('gray')">
<p>
	<canvas width="100" height="100" ondragenter="event.preventDefault()" ondragover="return false" ondrop="paint(event.dataTransfer.getData('text/plain'))">Canvas</canvas>
</p>
</body>
</html>