Javascript determines whether a web page is accessed by a mobile phone or a computer

var system ={};  
    var p = navigator.platform;       
    system.win = p.indexOf("Win") == 0;  
    system.mac = p.indexOf("Mac") == 0;  
    system.x11 = (p == "X11") || (p.indexOf("Linux") == 0);     
    if(system.win||system.mac||system.xll){//If the computer jumps to baidu & NBSP;
        window.location.href="http://www.baidu.com/";  
    }else{  //If it's a phone, jump to Google
        window.location.href="http://www.google.cn/";  
    }