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

namespace 测试控制台
{
    class Program
    {
        static void Main(string[] args)
        {
            Class2 o = new Class2();
            o.MethodA();
            o.MethodB();
            Console.ReadLine();
        }

    }

    public class BaseCom
    {
        public virtual void MethodA()
        {
            Console.WriteLine("BaseCom MethodA");
        }

        public virtual void MethodB()
        {
            Console.WriteLine("BaseCom MethodB");
        }

    }

    public class Class1:BaseCom
    {
        public void MethodA()
        {
            Console.WriteLine("Class1 MethodA");
        }

        public override void MethodB()
        {
            Console.WriteLine("Class1 MethodB");
        }
    }

    public class Class2 : Class1
    {
        public new  void MethodA()
        {
            Console.WriteLine("Class2 MethodA");
        }

    }
}

答案：

Class2 MethodA
class1 MethodB