is小实例

using System;using System.Collections.Generic;using System.Linq;using System.Text;namespace IS{    class Program    {        static void Main(string[] args)        {            IPerson admin = new Admin();            Class1 c1 = new Class1();            if (c1 is object )            {                Console.WriteLine("c1 是 object");            }            if (admin is Admin)            {                Console.WriteLine("admin 是管理员");            }            if (admin is Person)            {                Console.WriteLine("admin 是一个人");            }            if (admin is IAdmin)            {                Console.WriteLine("admin 是管理员接口");            }            if (admin is IPerson)            {                Console.WriteLine("admin 是一个人的接口");            }            if (admin is IZhangsan)            {                Console.WriteLine("admin 是张三");            }            admin = new Zhangsan();//多态            if (admin is IZhangsan)            {                Console.WriteLine("admin 是张三");            }            Console.ReadKey();        }    }    public class Class1    { }    public class Person : IPerson    {     }    public class Admin : Person,IAdmin    {     }    public interface IPerson    {     }    public interface IAdmin    { }    public interface IZhangsan    { }    public class Zhangsan : Person, IZhangsan    {     }}