private Souce orderOneTypeOfSouce(Souce souce)
        {
            Console.WriteLine();
            Console.WriteLine("Please type the name of the souce.");
            string souceName = Console.ReadLine();

            souce = souce.getSouce(souceName);

            while (souce == null)
            {
                Console.WriteLine("Wrong souce. Type again.");
                souceName = Console.ReadLine();
                souce     = new Souce();
                souce     = souce.getSouce(souceName);
            }

            Console.WriteLine();
            Console.WriteLine("How many " + souceName + " souces?");
            string souceNumber = Console.ReadLine();

            int number = getNumberOfItems(ref souceNumber);

            souce.no = number;
            return(souce);
        }
        private void takePizzaOrder(Order order, ref Pizza pizza, ref string response)
        {
            if (isPositiveResponse(response))
            {
                pizza = orderOneTypeOfPizza(pizza);
                order.pizzas.Add(pizza);

                while (isPositiveResponse(response))
                {
                    Console.WriteLine("Do you want to order another pizza? (Y/N)");
                    response = Console.ReadLine();

                    if (isPositiveResponse(response))
                    {
                        pizza = orderOneTypeOfPizza(pizza);
                        order.pizzas.Add(pizza);
                    }
                }
            }

            Console.WriteLine();
            Console.WriteLine("Do you want to order souce for your pizza? (Y/N)");

            Souce souce = new Souce();

            souce.displaySouceNameAndPrice();

            Console.WriteLine();
            response = Console.ReadLine();

            if (isPositiveResponse(response))
            {
                souce = orderOneTypeOfSouce(souce);
                order.souces.Add(souce);

                while (isPositiveResponse(response))
                {
                    Console.WriteLine("Do you want to order another souce? (Y/N)");
                    response = Console.ReadLine();

                    if (isPositiveResponse(response))
                    {
                        souce = orderOneTypeOfSouce(souce);
                        order.souces.Add(souce);
                    }
                }
            }
        }