private void GetHallState(AsyncType asyncType)
 {
     if (SelectedEvent != null)
     {
         SeatIndex[] seats;
         switch (asyncType)
         {
             case AsyncType.NoAsync:
                 IHallStateService syncProxy = new ChannelFactory<IHallStateService>("HallStateEP").CreateChannel();
                 seats = syncProxy.GetHallState(SelectedEvent.EventID);
                 ShowAvailableSeats(seats);
                 break;
         }
     }
     else
     {
         ShowAvailableSeats(null);
     }
 }