public void Menu()
        {
            LoginAdmin();
            do
            {
                Console.Clear();
                Console.WriteLine("---------------------------------------");
                Console.WriteLine("|     WELCOME TO DAEBAK BOOKSTORE     |");
                Console.WriteLine("|-------------------------------------|");
                Console.WriteLine("|1. BOOKS                             |");
                Console.WriteLine("|2. EMPLOYEE                          |");
                Console.WriteLine("|3. TRANSACTION                       |");
                Console.WriteLine("|4. TRANSACTION DETAIL                |");
                Console.WriteLine("|5. EXIT                              |");
                Console.WriteLine("---------------------------------------\n");
                Console.Write("Enter Your Choice : ");
                pilih = Console.ReadLine();
                Console.WriteLine("\n");
                switch (pilih)
                {
                case "1":
                    Book bk = new Book();
                    bk.BookMenu();
                    Menu();
                    break;

                case "2":
                    Employee emp = new Employee();
                    emp.EmployeeMenu();
                    Menu();
                    break;

                case "3":
                    Transaction tr = new Transaction();
                    Menu();
                    break;

                case "4":
                    Transaction_Detail td = new Transaction_Detail();
                    Menu();
                    break;

                case "5":
                    Console.WriteLine("Thank You So Much, Have A Nice Day!");
                    Console.ReadLine();
                    break;

                default:
                    Console.WriteLine("Wrong Input");
                    Console.ReadLine();
                    break;
                }
            } while (pilih != "5");
        }