c#簡單工廠設計模式

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

namespace _03簡單工廠設計模式
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("請輸入您想要的筆記本品牌");
            string brand = Console.ReadLine();
            NoteBook nb = GetNoteBook(brand);
            nb.SayHello();
            Console.ReadKey();
        }


        /// <summary>
        /// 簡單工廠的核心 根據使用者的輸入建立物件賦值給父類
        /// </summary>
        /// <param name="brand"></param>
        /// <returns></returns>
        public static NoteBook GetNoteBook(string brand)
        {
            NoteBook nb = null;
            switch (brand)
            {
                case "Lenovo": nb = new Lenovo();
                    break;
                case "IBM": nb = new IBM();
                    break;
                case "Acer": nb = new Acer();
                    break;
                case "Dell": nb = new Dell();
                    break;
            }
            return nb;
        }
    }

    public abstract class NoteBook
    {
        public abstract void SayHello();
    }

    public class Lenovo : NoteBook
    {
        public override void SayHello()
        {
            Console.WriteLine("我是聯想筆記本，你聯想也別想");
        }
    }


    public class Acer : NoteBook
    {
        public override void SayHello()
        {
            Console.WriteLine("我是鴻基筆記本");
        }
    }

    public class Dell : NoteBook
    {
        public override void SayHello()
        {
            Console.WriteLine("我是戴爾筆記本");
        }
    }

    public class IBM : NoteBook
    {
        public override void SayHello()
        {
            Console.WriteLine("我是IBM筆記本");
        }
    }
}