用javascript让图片每秒移动一下的问题，新手请求帮助
新手请求；
<html><head><title></title><script type="text/javascript">//让图片每秒左移10像素 var imgdo = null; function imgmove(){ imgdo = document.getElementById("imgdo"); imgdo.style.left = leftpx; imgdo.style.left = leftpx - 10; window.setTimeout('imgmove()',1000); } window.setTimeout('imgmove()',100)</script></head><body><img src="ic_launcher.png" style="position :absolute ;left : 400px; top:400px" id="imgdo" /></body></html><html><head><title></title><script type="text/javascript">//让图片每秒左移10像素 var imgdo = null; function imgmove(){ imgdo = document.getElementById("imgdo"); leftpx = parseInt(imgdo.style.left); imgdo.style.left = leftpx - 10 + 'px'; window.setTimeout('imgmove()',1000); } window.setTimeout(imgmove, 100)</script></head><body><img src="http://avatar.profile.csdn.net/8/D/B/2_tankun2011.jpg" style="position :absolute ;left : 400px; top:400px" id="imgdo" /></body></html>