public IActionResult GuessingGame()
        {
            int    luckyNr        = GuessingGameUtility.GetNewRandom();
            string initialMessage = "Guess a number between 1 and 100!";

            //save luckyNr in Session
            HttpContext.Session.SetInt32("LuckyNumber", luckyNr);

            //save NrofGuesses in Cookie
            CookieOptions option = new CookieOptions();

            option.Expires = DateTime.Now.AddMinutes(1);
            Response.Cookies.Append("NrOfGuesses", "0", option);

            //information to view
            //ViewBag.LuckyNumber = luckyNr;
            ViewBag.NrOfGuesses = 0;

            ViewBag.message = TempData["message"] == null ? initialMessage : TempData["message"];

            return(View());
        }