易百教程

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace MyAplication {
   class Demo {
      static void Main(string[] args) {
         // Father class
         Father f = new Father();
         f.Display();

         // Son class
         Son s = new Son();
         s.Display();
         s.DisplayOne();

         Console.ReadKey();
      }

      class Father {
         public void Display() {
            Console.WriteLine("Display");
         }
      }

      class Son : Father {
         public void DisplayOne() {
            Console.WriteLine("DisplayOne");
         }
      }
   }
}