应用程序

class Program

    {

        static void Main(string[] args)

        {

            Console.WriteLine("请选择人种：1-中国人，2-美国人 :");

            Person person = null;

            string personType = Console.ReadLine();

            switch (personType)

            {

                case "1":

                    person = new Chinese();

                    Console.WriteLine("中国人诞生了 ");

                    person.CreateLanguage();//为该人种建立语言

                    Console.WriteLine("中国人创建了汉语 ");

                    break;

                case "2":

                    person = new Englishman();

                    Console.WriteLine("英国人诞生了 ");

                    person.CreateLanguage();

                    Console.WriteLine("英国人创建了英语 ");

                    break;

                default:

                    Console.WriteLine("没有此种人！");

                    break;

            }

            string input = "";

            while (input != "Quit")

            {

                Console.Write("请输入词汇或者 Quit：");

                input = Console.ReadLine();

                person.Speak(input);

            }

        }

抽象人、语言类组

  public abstract class Person

    {

        protected Language language;

        abstract public void CreateLanguage();

        public void Speak(string words)

        {

            switch (words)

            {

                case "HelloWorld":

                    Console.WriteLine("Person ("+this.GetType()+") speak:"+language.HelloWorld);

                    break;

                case "Sorry":

                    Console.WriteLine("Person (" + this.GetType() + ") speak:" + language.Sorry);

                    break;

                default:

                    Console.WriteLine("Did not find the words!");

                    break;

            }

        }

    }

   public abstract class Language

    {

        protected string helloWorld;

        protected string sorry;

        public string HelloWorld

        {

            get { return helloWorld; }

            set { helloWorld = value; }

        }

        public string Sorry

        {

            get { return sorry; }

            set { sorry = value; }

        }

    }

英国人、英语类组

    public class Englishman : Person

    {

        public override void CreateLanguage()

        {

            language = new EnglishLanguage();

        }

    }

   public class EnglishLanguage : Language

    {

        public EnglishLanguage()

        {

            helloWorld = "Hello World !";

            sorry = "Sorry !";

        }

    }

中国人、汉语类组

    public class Chinese : Person

    {

        public override void CreateLanguage()

        {

            language = new ChineseLanguage();

        }

    }

    public class ChineseLanguage : Language

    {

        public ChineseLanguage()

        {

            helloWorld = "世界你好！";

            sorry = "对不起！";

        }

    }