using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
 
namespace ConsoleApplication1
{
 class Program
 {
 abstract public class Test
 {
 public virtual void Prinf()
 {
 Console.WriteLine("Abstract Printf...");
 }
 
 }
 public class Class1 : Test
 {
 public override void Prinf()
 {
 
 Console.WriteLine("Class One Override Printf...");
 }
 }
 public class Class2 : Test
 {
 public new void Prinf()
 {
 
 Console.WriteLine("Class Two New Printf...");
 }
 }
 
 static void Main(string[] args)
 {
 Class1 cls1 = new Class1();
 Class2 cls2 = new Class2();
 cls1.Prinf();
 cls2.Prinf();
 ((Test)cls1).Prinf();
 ((Test)cls2).Prinf();
 Console.ReadLine();
 }
 }
}

class Base 
{
	public virtual void F1() 
	{
	Console.WriteLine("Base's virtual function F1");
	}
	public virtual void F2() 
	{
	Console.WriteLine("Base's virtual fucntion F2");
	}
}
class Derived:Base 
{
	public override void F1() 
	{
	Console.WriteLine("Derived's override function F1");
	}
	public new void F2() 
	{
	Console.WriteLine("Derived's new function F2");
	}
}
class Program 
{
	public static void Main(string[] args) 
	{
	Base b1 = new Derived();
	//由于子類覆蓋了父類的方法，因此這里調用的是子類的F1方法。也是OO中多態的體現 
	b1.F1();
	//由于在子類中用new隱藏了父類的方法，因此這里是調用了隱藏的父類方法 
	b1.F2();
	}
}