var gIE = getIE();
      alert(gIE.version)
    function getIE() {
      var rmsie = /(msie) ([\w.]+)/;
      var ua = navigator.userAgent.toLowerCase();
      var match = rmsie.exec(ua)
      var result = {};
      if (match && match.length > 0) {
        result = { browser: match[1] || "", version: match[2] || "0" }
      }
      return result;
    }

<meta http-equiv="x-ua-compatible" content="IE=9;IE=8" />

<meta http-equiv="x-ua-compatible" content="IE=9,8" /> 

<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />