<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style>
.hack1{width:400px;_width:200px;height:20px;background:#F00}
.hack2{width:400px;*width:300px;height:20px;background:#F00}
.hack3{width:400px;width:300px\0;height:20px;background:#F00}
.hack4{width:400px;width:300px\9\0;height:20px;background:#F00}
.hack5{width:400px;width:300px\9;height:20px;background:#F00}
.hack6{width:300px!important;width:400px;height:20px;background:#F00}
</style>
</head>
<body>
<div class="hack1">'_' 只适用于IE6</div>
<br />
<div class="hack2">'*' 适用与IE6,7</div>
<br />
<div class="hack3">'\0' 适用与IE8</div>
<br />
<div class="hack4">'\9\0' 适用与IE9</div>
<br />
<div class="hack5">'\9' 区别IE和其他浏览器</div>
<br />
<div class="hack6">'!important' 提高CSS优先级,IE6不能识别</div>
</body>
</html>