public int CalculateAvailableTickets(Event selectedEvent) { // returns a count of available tickets int tickets = 0; int maxTickets = selectedEvent.MaxSeats; try { // check if there are any tickets reserved already if (0 != EventAccessor.RetrieveCountEventIDInRoomEvents(selectedEvent.EventID)) { // if there is, subtract that amount from the maximum amount tickets = maxTickets - EventAccessor.RetrieveCountOfPurchasedTickets(selectedEvent.EventID); } else { // none have been purchased yet, all the tickets remain tickets = maxTickets; } } catch (Exception) { throw; } return(tickets); }