public ActionResult Create(VacationManagement.VacationRequest vacationRequest)
        {
            String currentUserId = User.Identity.GetUserId();

            if (ModelState.IsValid)
            {
                String statusMessage;

                bool result = false;

                if (vacationRequest.VacationEndDate >= vacationRequest.VacationStartDate)
                {
                    if (DateTime.Now.Year == vacationRequest.getVacationStartDate().Year && DateTime.Now.Year == vacationRequest.getVacationEndDate().Year)
                    {
                        //Constructor VacationRequest
                        VacationManagement.VacationRequest vr = new VacationManagement.VacationRequest(currentUserId, vacationRequest.VacationStartDate, vacationRequest.VacationEndDate);

                        //start validate then insert into db
                        result = vr.InsertIntoDB();

                        if (result)
                        {
                            TempData["success"] = "Der Urlaubsantrag wurde erfolgreich angelegt.";
                        }
                    }
                    else
                    {
                        ErrorState.ErrorStateInstance.setError(ErrorState.VACATION_REQUEST_NOT_IN_CURRENT_YEAR);
                    }
                }
                else
                {
                    ErrorState.ErrorStateInstance.setError(ErrorState.END_DATE_BEFORE_START_DATE);
                }

                int lastError = ErrorState.ErrorStateInstance.getLastError();
                if (lastError != ErrorState.OK )
                {
                    TempData["error"] = "Leider konnte ihr Urlaubsantrag nicht erstellt werden. " + ErrorState.ErrorStateInstance.getErrorMessage(lastError);
                }
            }

            return RedirectToAction("Index", GetVacationRequests());
        }