08-工厂方法

1. 简介

　　工厂方法：符合依赖倒置原则、单一职责、开闭原则。

　　与简单工厂的区别：简单工厂是在一个工厂里生成多个不同的类，而工厂方法是一个对象对应一个生成工厂，这些工厂都实现了一个共同的接口IFactory，很好的符合了依赖倒置原则、单一职责、开闭原则， 每个工厂只负责创建对象。

2. 核心代码

  public interface IFactory
    {
        IPeople CreateInstance();
    }

  public class ChineseFactory : IFactory
    {
        public IPeople CreateInstance()
        {
            return new Chinese();
        }
    }

  public class JanpaneseFactory : IFactory
    {
        public IPeople CreateInstance()
        {
            return new Janpanese();
        }
    }

 public class AmericaFactory : IFactory
    {
        public IPeople CreateInstance()
        {
            return new America();
        }
    }

static void Main(string[] args)
        {
            IFactory iFactory1 = new ChineseFactory();
            IFactory iFactory2 = new AmericaFactory();
            IFactory iFactory3 = new JanpaneseFactory();

            IPeople iPeople1 = iFactory1.CreateInstance();
            IPeople iPeople2 = iFactory2.CreateInstance();
            IPeople iPeople3 = iFactory3.CreateInstance();


            iPeople1.Eating();
            iPeople2.Eating();
            iPeople3.Eating();

            Console.ReadKey();

        }