private void DisplayPurchaseMenu() { Console.Clear(); Console.WriteLine(); Console.WriteLine("Products"); foreach (var productItem in _ProductMenu) { Console.WriteLine($"{productItem.Key} - {productItem.Value}"); } OutputCurrentAmount(); Console.WriteLine("Please select a product to buy:"); var input = Console.ReadLine(); if (string.IsNullOrWhiteSpace(input)) { return; } if (int.TryParse(input, out var productId)) { _vendingMachine.Purchase(productId); } }