多态之虚方法

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

namespace ConsoleApplication4
{
    class Program
    {
        static void Main(string[] args)
        {            
            Chinese c1 = new Chinese("韩梅梅");
            Chinese c2 = new Chinese("李雷");
            Japanese j1 = new Japanese("树下");
            Japanese j2 = new Japanese("田中");
            Korea k1 = new Korea("金秀贤");
            Korea k2 = new Korea("金秀贤2");
            American a1 = new American("科比1");
            American a2 = new American("科比2");
            Person[] pers = {c1,c2,j1,j2,k1,k2,a1,a2};

            for (int i = 0; i < pers.Length; i++)
            {
                //if(pers[i] is Chinese)
                //{
                //    ((Chinese)pers[i]).SayHello();
                //}
                //else if(pers[i] is Japanese)
                //{
                //    ((Japanese)pers[i]).SayHello();
                //}
                //else if(pers[i] is Korea)
                //{
                //    ((Korea)pers[i]).SayHello();
                //}
                //else if(pers[i] is American)
                //{
                //    ((American)pers[i]).SayHello();
                //}
                pers[i].SayHello();
            }
            Console.ReadKey();
        }
    }
    public class Person
    {
        private string _name;//字段

        public string Name//属性
        {
            get{return _name;}
            set{_name = value;}
        }

        public Person(string name)//构造函数
        {
            this.Name = name;
        }

        public virtual void SayHello()//方法 virtual 虚方法，这个方法可以被子类重写
        {
            Console.WriteLine("我是人类");
        }
    }

    public class Chinese:Person
    {
        public Chinese(string name):base(name) //调用父类构造函数，外面传进一个name，传给父类一个name
        {
            //不用写代码，父类的构造器已经赋值给属性Name
        }
        public override void SayHello()//override重写 父类方法
        {
            Console.WriteLine("我是中国人，我叫{0}",this.Name);
        }        
    }    
    public class Japanese:Person
    {
        public Japanese(string name)
            :base(name)
        { }
        public override void SayHello()
        {
            Console.WriteLine("我是霓虹人，我叫{0}",this.Name);
        }
    }
    public class Korea:Person
    {
        public Korea(string name)
            :base(name)
        { }
        public override void SayHello()
        {
            Console.WriteLine("我是棒子人，我叫{0}",this.Name);
        }
    }
    public class American:Person
    {
        public American(string name)
            :base(name)
        { }
        public override void SayHello()
        {
            Console.WriteLine("我是米国人，我叫{0}",this.Name);
        }
    }
}