get ie version by google

gistfile1.txt

tn_.labs.userAgent.browser.getIEVersion_ = function(a) {
    var b = /rv: *([\d\.]*)/.exec(a);
    if (b && b[1]) return b[1];
    b = "";
    var c = /MSIE +([\d\.]+)/.exec(a);
    if (c && c[1])
        if (a = /Trident\/(\d.\d)/.exec(a), "7.0" == c[1])
            if (a && a[1]) switch (a[1]) {
                case "4.0":
                    b = "8.0";
                    break;
                case "5.0":
                    b = "9.0";
                    break;
                case "6.0":
                    b = "10.0";
                    break;
                case "7.0":
                    b = "11.0"
            } else b = "7.0";
            else b = c[1];
    return b
};
getIeVersion_(navigator.userAgent)