苗景云的博客

    var Sys = {}; 
        var ua = navigator.userAgent.toLowerCase(); 
        var s; 
        (s = ua.match(/msie ([\d.]+)/))? Sys.ie = s[1]: 
...

1. 五大浏览器判断

<script type="text/javascript">       
    var Sys = {}; 
...