js判断IE浏览器版本

if(navigator.userAgent.indexOf("MSIE")>0){   
      if(navigator.userAgent.indexOf("MSIE 6.0")>0){   
        alert("ie6浏览器");    
      }   
      if(navigator.userAgent.indexOf("MSIE 7.0")>0){  
        alert("ie7浏览器");   
      } 
    if(navigator.userAgent.indexOf("MSIE 8.0")>0){  
        alert("ie8浏览器");   
      }   
      if(navigator.userAgent.indexOf("MSIE 9.0")>0){  
        alert("ie9浏览器");  
      }   
    } 
//判断浏览器版本低于IE8
 if(navigator.userAgent.indexOf("MSIE")>0){
                if(navigator.userAgent.indexOf("MSIE 6.0")>0 || navigator.userAgent.indexOf("MSIE 7.0")>0 || navigator.userAgent.indexOf("MSIE 8.0")>0){
                    alert(alert("低于ie8浏览器"); )
                }
            }

//判断是否为移动端设备
var mobileAgent = new Array("iphone", "ipod", "ipad", "android", "mobile", "blackberry", "webos", "incognito", "webmate", "bada", "nokia", "lg", "ucweb", "skyfire");
    var browser = navigator.userAgent.toLowerCase();
    var isMobile = false;
    for (var i=0; i<mobileAgent.length; i++){
        if (browser.indexOf(mobileAgent[i])!=-1){
            isMobile = true;
            $(".bodya .u1").css("background","green");
         }
    }