using System;

public class Program

{

     public void Start()

        {

            int choice = -1;

            while(choice != 0 )

            {

                ShowMenu();

                choice = int.Parse(Console.ReadLine());

​

                switch (choice)

                {

                    case 0:

                        //donothing

                        break;

                    case 1:

                        Console.WriteLine(" You choose 1.");

                        break;

                    case 2:

                        Console.WriteLine(" You choose 2.");

                        break;

                }

            }

        }

        private void ShowMenu()

        {

            Console.WriteLine("Please choose your choice 0, 1, 2");

​

        }

        public static void Main(string[] args)

        {

            Program P = new Program();

            P.Start();

​

        }

}