public IActionResult CheckDestinationsId()
        {
            var inputModel = new FlightsByDestinationsIdInputModel();

            inputModel.StartDestinationItems = this.destinationsService.GetAllStartCountriesForFlightsAsKeyValuePairs();
            inputModel.EndDestinationItems   = this.destinationsService.GetAllEndCountriesForFlightsAsKeyValuePairs();

            return(this.View(inputModel));
        }
        public IActionResult CheckDestinationsId(FlightsByDestinationsIdInputModel inputModel)
        {
            if (!this.ModelState.IsValid)
            {
                inputModel.StartDestinationItems = this.destinationsService.GetAllStartCountriesForFlightsAsKeyValuePairs();
                inputModel.EndDestinationItems   = this.destinationsService.GetAllEndCountriesForFlightsAsKeyValuePairs();
            }

            return(this.RedirectToAction("AllByDestinationsId", new { startDestinationId = inputModel.StartPointId, endDestinationId = inputModel.EndPointId, numberOfTourists = inputModel.NumberOfTourists }));
        }