JS判断浏览器类型和版本

<script type="text/javascript">
var Sys = {};
var ua = navigator.userAgent.toLowerCase();
var s;
(s = ua.match(/msie ([\d.]+)/)) ? Sys.ie = s[1] :
(s = ua.match(/firefox\/([\d.]+)/)) ? Sys.firefox = s[1] :
(s = ua.match(/chrome\/([\d.]+)/)) ? Sys.chrome = s[1] :
(s = ua.match(/opera.([\d.]+)/)) ? Sys.opera = s[1] :
(s = ua.match(/version\/([\d.]+).*safari/)) ? Sys.safari = s[1] : 0;
 
//以下进行测试
if (Sys.ie) document.write("IE: " + Sys.ie);
if (Sys.firefox) document.write("Firefox: " + Sys.firefox);
if (Sys.chrome) document.write("Chrome: " + Sys.chrome);
if (Sys.opera) document.write("Opera: " + Sys.opera);
if (Sys.safari) document.write("Safari: " + Sys.safari);
</script>