js判断手机或者PC的几个例子

例子一

<script>
function browserRedirect() {
    var sUserAgent = navigator.userAgent.toLowerCase();
    var bIsIpad = sUserAgent.match(/ipad/i) == "ipad";
    var bIsIphoneOs = sUserAgent.match(/iphone os/i) == "iphone os";
    var bIsMidp = sUserAgent.match(/midp/i) == "midp";
    var bIsUc7 = sUserAgent.match(/rv:1.2.3.4/i) == "rv:1.2.3.4";
    var bIsUc = sUserAgent.match(/ucweb/i) == "ucweb";
    var bIsAndroid = sUserAgent.match(/android/i) == "android";
    var bIsCE = sUserAgent.match(/windows ce/i) == "windows ce";
    var bIsWM = sUserAgent.match(/windows mobile/i) == "windows mobile";
    if (!(bIsIpad || bIsIphoneOs || bIsMidp || bIsUc7 || bIsUc || bIsAndroid || bIsCE || bIsWM) ){
     window.location.href='http://www.111cn.net';
    }else{
  //window.location.href='http://m.111cn.net'; 
 }
}
$(function(){
 browserRedirect();
});
</script>

例子2

<script type="text/javascript">
/*
    PC841适配跳转
*/
(function(){
    var reWriteUrl = function(url){
        if(url){
            var Splits = url.split("/"),siteName=window.location.pathname;
            if(typeof siteName!=="undefined"){
                return "http://m.111cn.net"+siteName;
            }
        }
    };
    if(/Android|webOS|iPhone|iPad|Windows Phone|iPod|BlackBerry|SymbianOS|Nokia|Mobile/i.test(navigator.userAgent)){
        var url=window.location.href;
        var pathname=window.location.pathname;
        if(url.indexOf("?mobile")<0){
        try{
            window.location.href=reWriteUrl(url);
        }catch(e){}
        }
    };
})();
</script>

注意，如果给搜索引擎看的话我们在文件头加入

<meta http-equiv="mobile-agent" content="format=xhtml; url=http://m.111cn.net" />
<meta http-equiv="mobile-agent" content="format=html5; url=http://m.111cn.net" />

意思是告诉搜索引擎移动蜘蛛抓取的是手机版本的．