public override void OnActionExecuting(ActionExecutingContext filterContext)
        {
            HowToDbEntities _db  = new HowToDbEntities();
            users           user = LoginHelper.CurrentUser();

            if (!LoginHelper.IsLoggedIn() || user.categoriesId != (int)categories.admin)
            {
                filterContext.Result = new RedirectToRouteResult(
                    new RouteValueDictionary {
                    { "Controller", "Account" }, { "Action", "Login" }
                });
            }
            else
            {
                var userPassword = SHA.GenerateSHA512String(user.password);
                var userFromDb   = _db.users.FirstOrDefault(e => e.password == userPassword && e.email == user.email);
                if (userFromDb == null)
                {
                    filterContext.Result = new HttpStatusCodeResult(HttpStatusCode.Forbidden);
                }
            }
            base.OnActionExecuting(filterContext);
        }