/// <summary> /// calls the ConsoleView.DisplayGetNumberOfUnitsToSell method and the SubtractProduct method if a valid integer is returned /// </summary> private void Sell() { if (_salesperson.CurrentStock != null) { int numberOfUnits = _consoleView.DisplayGetNumberOfUnitsToSell(_salesperson.CurrentStock); _salesperson.CurrentStock.SubtractProducts(numberOfUnits); if (_salesperson.CurrentStock.OnBackorder) { _consoleView.DisplayBackOrderNotification(_salesperson.CurrentStock, numberOfUnits); } } else { _consoleView.DisplayObjectError("product"); } }