private void Seat_Button_Click(object sender, RoutedEventArgs e)
 {
     if (flightDataGrid.SelectedItems != null && flightDataGrid.SelectedItems.Count > 0)
     {
         var seatChart = new SeatChart(flightDataGrid.SelectedItems[0]);
         NavigationService.Navigate(seatChart);
     }
 }
        private void SelectSeat_Button_Click(object sender, RoutedEventArgs e)
        {
            if (!Enum.TryParse(TicketClassCombobox, out SeatClass ticketClass))
            {
                ticketClass = SeatClass.Economy;
            }
            var user = new User()
            {
                UserDao = new UserDao()
                {
                    FirstName = FirstNameTextbox,
                    LastName  = LastNameTextbox,
                    Age       = AgeTextbox.ToShortOrDefault()
                }
            };
            var seatChart = new SeatChart(BookingFlightInfo, user, ticketClass);

            NavigationService.Navigate(seatChart);
        }