browserdetect.js

window.browserDetect = {
    init: function () {
        this.browser = this.searchString(this.dataBrowser) || "Other";
        this.version = this.searchVersion(navigator.userAgent) || this.searchVersion(navigator.appVersion) || "Unknown";

        // detect IE 11
        if (this.browser == 'Explorer' && this.version == '7' && navigator.userAgent.match(/Trident/i)) {
            this.version = this.searchVersionIE();
        }
    },
    searchString: function (data) {
        for (var i = 0; i < data.length; i++) {
            var dataString = data[i].string;
            this.versionSearchString = data[i].subString;

            if (dataString.indexOf(data[i].subString) != -1) {
                return data[i].identity;
            }
        }
    },
    searchVersion: function (dataString) {
        var index = dataString.indexOf(this.versionSearchString);
        if (index == -1)
            return;
        return parseFloat(dataString.substring(index + this.versionSearchString.length + 1));
    },
    searchVersionIE: function () {
        var ua = navigator.userAgent.toString().toLowerCase(), match = /(trident)(?:.*rv:([\w.]+))?/.exec(ua) || /(msie) ([\w.]+)/.exec(ua) || ['', null, -1], ver;
        try  {
            ver = match[2].split('.')[0]; // version
        } catch (err) {
            ver = 'unknown'; //
        }
        return ver;
    },
    dataBrowser: [
        { string: navigator.userAgent, subString: "Chrome", identity: "Chrome" },
        { string: navigator.userAgent, subString: "MSIE", identity: "Explorer" },
        { string: navigator.userAgent, subString: "Trident", identity: "Explorer" },
        { string: navigator.userAgent, subString: "Firefox", identity: "Firefox" },
        { string: navigator.userAgent, subString: "Safari", identity: "Safari" },
        { string: navigator.userAgent, subString: "Opera", identity: "Opera" }
    ]
};

window.browserDetect.init();