settimeout.html


<html >
	<head>
		<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
		<title>New Web Project</title>
		
	</head>
	<body>
		<div style="height: 20px;width: 400px;border: 1px solid gray;padding: 2px">
			<div style="height:20px;width:0px;background-color: red;" id="div2">
 
			</div>
		</div>
		<br />
		<input type="button" value="开始" οnclick="doStart()" />
		<input type="button" value="停止" οnclick="doStop()" />
		<script type="text/javascript">
		
			var timer = null;
			var width = 0;
			function doStart() {
				timer = window.setTimeout(onChange(), 10);
			}
		 
			function doStop() {
				window.clearTimeout(timer);
			}
		 
			function onChange() {
				if(width == 400) {
					window.clearTimeout(timer);
				}else {
					width += 1;
					document.getElementById("div2").style.width = width + "px";
					
					timer = window.setTimeout(onchange(), 10);
				}
			}
		 
		</script>
	</body>
</html>
 