设计模式-代理模式

Proxy pattern

代理模式（Proxy）为另一个对象提供一个替身或占位符以控制对这个对象的访问，简而言之就是用一个对象来代表另一个对象。

   abstract class Subject
    {
        public abstract void Request();
    }

    class RealSubject : Subject
    {
        public override void Request()
        {
            Console.WriteLine("真实的请求");
        }
    }

    class Proxy : Subject
    {
        RealSubject realSubject;
        public override void Request()
        {
            if (realSubject == null)
            {
                realSubject = new RealSubject();
            }

            realSubject.Request();
        }
    }

客户端调用：

Proxy proxy = new Proxy();
proxy.Request();

学习示例：

  //送礼物
    interface GiveGift
    {
        void GiveDolls();
        void GiveFlowers();
        void GiveChocolate();
    }

    class Proxy : GiveGift
    {
        Pursuit gg;
        public Proxy(SchoolGirl mm)
        {
            gg = new Pursuit(mm);
        }

        public void GiveDolls()
        {
            gg.GiveDolls();
        }

        public void GiveFlowers()
        {
            gg.GiveFlowers();
        }

        public void GiveChocolate()
        {
            gg.GiveChocolate();
        }
    }

    class Pursuit : GiveGift
    {
        SchoolGirl mm;
        public Pursuit(SchoolGirl mm)
        {
            this.mm = mm;
        }
        public void GiveDolls()
        {
            Console.WriteLine(mm.Name + " 送你洋娃娃");
        }

        public void GiveFlowers()
        {
            Console.WriteLine(mm.Name + " 送你鲜花");
        }

        public void GiveChocolate()
        {
            Console.WriteLine(mm.Name + " 送你巧克力");
        }
    }

    class SchoolGirl
    {
        private string name;
        public string Name
        {
            get { return name; }
            set { name = value; }
        }
    }

客户端调用：

SchoolGirl jiaojiao = new SchoolGirl();
jiaojiao.Name = "李萌";

Proxy daili = new Proxy(jiaojiao);

daili.GiveDolls();
daili.GiveFlowers();
daili.GiveChocolate();

大话设计模式-程杰

http://www.cnblogs.com/hegezhou_hot/archive/2011/02/20/1958965.html