public ActionResult LogOff(int userID)
        {
            string ip = "";

            if (ViewBag.IPAddress != null)
            {
                ip = ViewBag.IPAddress.StringSafe();
            }

            UserType    user  = UserCache.GetFromCache(userID, ip);
            AccessModel model = new AccessModel();
            UserType    _user = new UserType();

            if (user != null)
            {
                _user = new UserType
                {
                    UserName     = "******",
                    UserID       = -1,
                    SessionStart = DateTime.Now
                };
            }
            bool bRet = model.LogOff(user);

            if (bRet)
            {
                UserCache.RemoveFromCache(user.UserID, "");
                UserCache.AddToCache(_user);
            }
            return(RedirectToAction("index", "home"));
        }