代码如下：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div id='box'></div>
<script>
var oBox = document.getElementById("box");
var maxLeft = utils.win('clientWidth')-oBox.offsetWidth;
var step = 5;
var timer = null;
//使用递归思想完成setTimeout的轮循动画：每一次在执行动画之前把上一次设置没用的定时器清除掉，节约我们的内存空间
function move(){
window.clearTimeout(timer);
var curLeft = utils.css(oBox,"left");
if(curLeft+step >= maxLeft){//边界判断
utils.css(oBox,"left",maxLeft);
return;
}
curLeft+=step;
utils.css(oBox,"left",curLeft);
timer = window.setTimeout(move,10)
}
move();
</script>
</body>
</html>