JS判断是否为移动端

var is_mobi = navigator.userAgent.toLowerCase().match(/(ipod|iphone|android|coolpad|mmp|smartphone|midp|wap|xoom|symbian|j2me|blackberry|wince)/i) != null;
      
    //检测是否移动设备来访
      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) { 
            return true;
         } else { 
            return false;
         } 
      }