<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
<style>
.demo
{
width:100px;
height:100px;
background:#000;
position:absolute;
left:100px;
}
</style>
<script>
$(document).ready(function(){
$("#left").click(function(){
$(".demo").stop(true,true).animate({"left":"-=50px"});
});
$("#right").click(function(){
$(".demo").stop(true,true).animate({"left":"+=50px"});
});
});
</script>
</head>
<body>
<input type="button" id="left" value="click before" />
<input type="button" id="right" value="click after"/>
<div></div>
</body>
</html>
