如何识别手机浏览器并跳转到指定网页？

<!---识别手机或电脑的js开始--->
<script language="javascript">
(function(){
var res = GetRequest();
var par = res['index'];
if(par!='gfan'){
var ua=navigator.userAgent.toLowerCase();
var contains=function (a, b){
if(a.indexOf(b)!=-1){return true;}
};
//将下面http://www.leqii.com改成你的wap手机版地址 如我的http://www.leqii.com
var toMobileVertion = function(){
window.location.href = 'http://www.leqii.com'
}

if(contains(ua,"ipad")||(contains(ua,"rv:1.2.3.4"))||(contains(ua,"0.0.0.0"))||(contains(ua,"8.0.552.237"))){return false}
if((contains(ua,"android") && contains(ua,"mobile"))||(contains(ua,"android") && contains(ua,"mozilla")) ||(contains(ua,"android") && contains(ua,"opera"))
||contains(ua,"ucweb7")||contains(ua,"iphone")){toMobileVertion();}
}
})();
function GetRequest() {
var url = location.search; //获取url中"?"符后的字串
var theRequest = new Object();
if (url.indexOf("?") != -1) {
var str = url.substr(1);
strs = str.split("&");
for(var i = 0; i < strs.length; i ++) {
theRequest[strs[i].split("=")[0]]=unescape(strs[i].split("=")[1]);
}
}
return theRequest;
}
</script>
<!---识别手机或电脑的js结束--->

来源：http://zhidao.baidu.com/link?url=n0uoQ1GTRjQYrZNJsp9n6pfm3bbcXpTPdpAl9ijS5xYh745izWDj-ghpXfi5ivn7GWZNe9fdStrRXyefD4pUi27RuPIFwATy1XUu8mbkLmC