JS判断浏览器类型

var userAgent = navigator.userAgent; //取得浏览器的userAgent字符串

   var isOpera = userAgent.indexOf("Opera") > -1; //判断是否Opera浏览器

   var isIE = userAgent.indexOf("compatible") > -1 && userAgent.indexOf("MSIE") > -1 && !isOpera; //判断是否IE浏览器

   var isEdge = userAgent.indexOf("Windows NT 6.1; Trident/7.0;") > -1 && !isIE; //判断是否IE的Edge浏览器

   var isFF = userAgent.indexOf("Firefox") > -1; //判断是否Firefox浏览器

   var isSafari = userAgent.indexOf("Safari") > -1 && userAgent.indexOf("Chrome") == -1; //判断是否Safari浏览器

   var isChrome = userAgent.indexOf("Chrome") > -1 && userAgent.indexOf("Safari") > -1; //判断Chrome浏览器

  

   if (isIE) 

   {

      var reIE = new RegExp("MSIE (\\d+\\.\\d+);");

      reIE.test(userAgent);

      var fIEVersion = parseFloat(RegExp["$1"]);

      if(fIEVersion == 7)

      { return "IE7";}

      else if(fIEVersion == 8)

      { return "IE8";}

      else if(fIEVersion == 9)

      { return "IE9";}

      else if(fIEVersion == 10)

      { return "IE10";}

      else if(fIEVersion == 11)

      { return "IE11";}

      else

      { return "0"}//IE版本过低

    }

      

    if (isFF) { return "FF";}

    if (isOpera) { return "Opera";}

    if (isSafari) { return "Safari";}

    if (isChrome) { return "Chrome";}

    if (isEdge) { return "Edge";}