JS判断每个浏览器版本

function checkBrowser()
{
 var browserName=navigator.userAgent.toLowerCase();
 //var ua = navigator.userAgent.toLowerCase();
 var Sys = {};
 var rtn = false;
 
    if(/msie/i.test(browserName) && !/opera/.test(browserName)){
        strBrowser = "IE: "+browserName.match(/msie ([\d.]+)/)[1];
  rtn = true;
        //return true;
    }else if(/firefox/i.test(browserName)){
        strBrowser = "Firefox: " + browserName.match(/firefox\/([\d.]+)/)[1];;
        //return false;
    }else if(/chrome/i.test(browserName) && /webkit/i.test(browserName) && /mozilla/i.test(browserName)){
        strBrowser = "Chrome: " + browserName.match(/chrome\/([\d.]+)/)[1];
        //return false;
    }else if(/opera/i.test(browserName)){
        strBrowser = "Opera: " + browserName.match(/opera.([\d.]+)/)[1];
        //return false;
    }else if(/webkit/i.test(browserName) &&!(/chrome/i.test(browserName) && /webkit/i.test(browserName) && /mozilla/i.test(browserName))){
        strBrowser = "Safari: ";
        //return false;
    }else{
        strBrowser = "unKnow,未知浏览器 ";
  //return false;
    }
 strBrowser =  "您当前使用的浏览器是：" + strBrowser ;
 //alert(strBrowser)
 return rtn;
}