public void InputProduct()
        {
            // Manufacturer input.
            Console.Write("Enter manufacturer of product: ");
            do
            {
                Manufacturer = Console.ReadLine();
                if (Manufacturer.All(char.IsLetterOrDigit))
                {
                    break;
                }
                else
                {
                    Console.WriteLine("Name of manufacturer should only consist of letters and digits!");
                }
            } while (Manufacturer == null);

            // Type of item input.
            Console.Write("Enter type of item: ");
            do
            {
                TypeOfItem = Console.ReadLine();
                if (TypeOfItem.All(char.IsLetter))
                {
                    break;
                }
                else
                {
                    Console.WriteLine("Type of product should only consist of letters!");
                }
            } while (TypeOfItem == null);

            // Price input.
            double tempPrice = new double();

            while (double.TryParse(Console.ReadLine(), out tempPrice) == false)
            {
                Console.Write("Wrong price input! Try again: ");
            }
            Price = tempPrice;

            // Dimension input.
            double tempDimension = new double();

            while (double.TryParse(Console.ReadLine(), out tempDimension) == false)
            {
                Console.Write("Wrong dimension input! Try again: ");
            }
            Dimension = tempDimension;
        }