<script type="text/javascript">
  function IsPC() {
      var userAgentInfo = navigator.userAgent;
      var Agents = ["Android", "iPhone",
                  "SymbianOS", "Windows Phone",
                  "iPad", "iPod"];
      var flag = true;
      for (var v = 0; v < Agents.length; v++) {
          if (userAgentInfo.indexOf(Agents[v]) > 0) {
              flag = false;
              break;
          }
      }
      return flag;
  }
  if (IsPC()) { 
         window.location ="http://www.baidu.com/";
  };
</script>

userAgentInfo.indexOf(Agents[v])：
//A.indexOf(array[i]):A元素是否存在于數(shù)組array里面；如果存在就會返回對應的下標，如果不存在則返回-1.
function IsPC(){
var userAgentInfo = navigator.userAgent;//使用navigator.userAgent來判斷瀏覽器類型。 
var Agents = new Array("Android", "iPhone", "SymbianOS", "Windows Phone", "iPad", "iPod"); 
var flag = true;
    for (var v = 0; v < Agents.length; v++) {
       if (userAgentInfo.indexOf(Agents[v]) >= 0) {
       flag = false;
       break;
       }
    }
   return flag;
}