public static void ProductOperationMenu()
        {
            Console.WriteLine("Please Select Product Operation");
            Console.WriteLine("a. Add a Product");
            Console.WriteLine("b. List all Products");
            Console.WriteLine("c. Search a Product");
            Console.WriteLine("d. Delete a Product");
            Console.WriteLine("e. Main Menu");
            char ch1 = Convert.ToChar(Console.ReadLine());

            switch (ch1)
            {
            case 'a':
                Console.WriteLine("Enter Product Name");
                var ProductName = Console.ReadLine();
                while (string.IsNullOrWhiteSpace(ProductName) || int.TryParse(ProductName, out _))
                {
                    Console.WriteLine("Please Enter Only Char and It can not be Empty");
                    ProductName = Console.ReadLine();
                }
                Console.WriteLine("Enter Short Code");
                var shortCode = Console.ReadLine();

                Console.WriteLine("Enter Description");
                var desc = Console.ReadLine();
                while (string.IsNullOrWhiteSpace(desc) || int.TryParse(desc, out _))
                {
                    Console.WriteLine("Please Enter Only Char and It can not be Empty");
                    desc = Console.ReadLine();
                }
                Console.WriteLine("Enter Price");
                int  price = -1;
                bool flag  = Int32.TryParse(Console.ReadLine(), out price);
                while (!flag || price <= 0)
                {
                    Console.WriteLine("Please Enter Only Number and It can not be Empty/can not be negetive");
                    flag = Int32.TryParse(Console.ReadLine(), out price);
                }
                Console.WriteLine("Enter Manufacture Name");
                var manufactureName = Console.ReadLine();
                while (string.IsNullOrWhiteSpace(manufactureName) || int.TryParse(manufactureName, out _))
                {
                    Console.WriteLine("Please Enter Only Char and It can not be Empty");
                    manufactureName = Console.ReadLine();
                }
                Console.WriteLine("Enter Category Name");
                var category = Console.ReadLine();
                while (string.IsNullOrWhiteSpace(category) || int.TryParse(category, out _))
                {
                    Console.WriteLine("Please Enter Only Char and It can not be Empty");
                    category = Console.ReadLine();
                }
                ProductOperation.AddProduct(ProductName, shortCode, desc, price, manufactureName, category);
                break;

            case 'b':
                ProductOperation.GetAllProduct();
                break;

            case 'c':
                Console.WriteLine("Enter Product Name");
                var SearchProductName = Console.ReadLine();
                while (string.IsNullOrWhiteSpace(SearchProductName) || int.TryParse(SearchProductName, out _))
                {
                    Console.WriteLine("Please Enter Only Char and It can not be Empty");
                    ProductName = Console.ReadLine();
                }
                ProductOperation.SearchProduct(SearchProductName);
                break;

            case 'd':
                Console.WriteLine("Enter Product Name");
                var DeleteProductName = Console.ReadLine();
                while (string.IsNullOrWhiteSpace(DeleteProductName) || int.TryParse(DeleteProductName, out _))
                {
                    Console.WriteLine("Please Enter Only Char and It can not be Empty");
                    DeleteProductName = Console.ReadLine();
                }
                ProductOperation.DeleteProduct(DeleteProductName);
                break;

            case 'e':
                StartMenu.Menu();
                break;

            default:
                Console.WriteLine("Invalid Selection!!");
                ProductOperationMenu();
                break;
            }
        }