<script>
          $(function(){
          var isIE78910=/mise/i.test(navigator.userAgent.toLowerCase());
          var isIE11=/trident/i.test(navigator.userAgent.toLowerCase());
          var isIE=(isIE78910 || isIE11);
  
          if(isIE){
             //todo
          }
          })();
      </script>

var islowIE8=false;
var isIE=/mise/i.test(navigator.userAgent.toLowerCase());
if (isIE) {
truevar ieVersion=/msie ([\d.]+)/.navigator.userAgent.toLowerCase();
trueieVersion = parseInt(ieVersion);
trueislowIE8= (ieVersion>8);
}
if (islowIE8){ 	//<=ie8的情况
true//todo..
}else{		 	//其他情况
true//todo..
}