JavaScript判断操作系统版本

        function detectOS() {
            var sUserAgent = navigator.userAgent;
            var isWin = (navigator.platform == "Win32") || (navigator.platform == "Windows");
            var isMac = (navigator.platform == "Mac68K") || (navigator.platform == "MacPPC") || (navigator.platform == "Macintosh") || (navigator.platform == "MacIntel");
            if (isMac) return "Mac";
            var isUnix = (navigator.platform == "X11") && !isWin && !isMac;
            if (isUnix) return "Unix";
            var isLinux = (String(navigator.platform).indexOf("Linux") > -1);
            if (isLinux) return "Linux";
            if (isWin) {
                var isWin2K = sUserAgent.indexOf("Windows NT 5.0") > -1 || sUserAgent.indexOf("Windows 2000") > -1;
                if (isWin2K) return "Win2000";
                var isWinXP = sUserAgent.indexOf("Windows NT 5.1") > -1 || sUserAgent.indexOf("Windows XP") > -1;
                if (isWinXP) return "WinXP";
                var isWin2003 = sUserAgent.indexOf("Windows NT 5.2") > -1 || sUserAgent.indexOf("Windows 2003") > -1;
                if (isWin2003) return "Win2003";
                var isWinVista = sUserAgent.indexOf("Windows NT 6.0") > -1 || sUserAgent.indexOf("Windows Vista") > -1;
                if (isWinVista) return "WinVista";
                var isWin7 = sUserAgent.indexOf("Windows NT 6.1") > -1 || sUserAgent.indexOf("Windows 7") > -1;
                if (isWin7) return "Win7";
            }
            return "other";
        }

        document.writeln("您的操作系统是：" + detectOS());