HTML5 - Beginners - Clear array using length.html

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width" />
</head>
<body bgcolor="black">
<div id="test"></div>
<canvas id="myCanvas" width="320" height="240" style="border:0px solid #d3d3d3;">
Use different browser.
</canvas>
	<script>
	var c=document.getElementById("myCanvas");
	var ctx=c.getContext("2d");


	gameloop=setInterval(doGameLoop,16);

	function doGameLoop(){
		myCanvas.height = window.innerHeight-32;
		myCanvas.width = window.innerWidth-32;
		ctx.fillStyle="rgb(0,0,0)";
		ctx.fillRect(0,0,c.width,c.height);
		ctx.fillStyle="rgb(255,255,255)";
		ctx.fillText("Javascript Html canvas example.",10,10); 

		var arr = [1,2,3,4,5,6,7,8,9,10];
		ctx.fillStyle='white';
		ctx.fillText("contents of array : "+arr,100,50);
		arr.length=0;
		ctx.fillText("contents after setting length to 0 : "+arr,100,100);

	}
</script>
</body>
</html>