js屏蔽pc端访问

<script type="text/javascript"> 
 //平台、设备和操作系统 
 var system ={ 
 win : false, 
 mac : false, 
 xll : false
 };
 //检测平台
 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){ 
 window.location.href="pc端访问的链接";
 }else{ 
 }
</script>