装饰模式

1.Decorrator中保存有一个Component，然后ConcoreteComponent中就可以给ConcoreteComponent添加一些职责

2.场景：我们现在用的手机功能很多，我就用Decorator模式实现一下对某个手机的GSP和蓝牙功能扩展

3.代码：

手机：

public abstract class AbstractCellPhone

    {

        public abstract string CallNumber();

        public abstract string SendMessage();

}

Nokia和Moto的手机：

public class NokiaPhone : AbstractCellPhone

    {

        public override string CallNumber()

        {

            return "NokiaPhone call sombody";

        }

 

        public override string SendMessage()

        {

            return "NokiaPhone send a message to somebody";

        }

    }

 

    public class MotoPhone : AbstractCellPhone

    {

        public override string CallNumber()

        {

            return "MotoPhone call sombody";

        }

 

        public override string SendMessage()

        {

            return "MotoPhone send a message to somebody";

        }

 }

装饰类：

public abstract class Decorator:AbstractCellPhone

    {

        AbstractCellPhone _phone;

 

        public Decorator(AbstractCellPhone phone)

        {

            _phone = phone;

        }

 

        public override string CallNumber()

        {

            return _phone.CallNumber();

        }

 

        public override string SendMessage()

        {

            return _phone.SendMessage();

        }

  }

GSP和蓝牙的职责扩展：

public class DecoratorGPS : Decorator

    {

        public DecoratorGPS(AbstractCellPhone phone)

            : base(phone)

        { }

 

        public override string CallNumber()

        {

            return base.CallNumber() + " with GPS";

        }

 

        public override string SendMessage()

        {

            return base.SendMessage() + " with GPS";

        }

    }

 

    public class DecoratorBlueTooth : Decorator

    {

        public DecoratorBlueTooth(AbstractCellPhone phone)

            : base(phone)

        { }

 

        public override string CallNumber()

        {

            return base.CallNumber() + " with BlueTooth";

        }

 

        public override string SendMessage()

        {

            return base.SendMessage() + " with BlueTooth";

        }

 }

客户端调用：

static void Main(string[] args)

        {

             AbstractCellPhone phone = new NokiaPhone();

            Console.WriteLine(phone.CallNumber());

            Console.WriteLine(phone.SendMessage());

            DecoratorGPS gps = new DecoratorGPS(phone);     //add GSP

            Console.WriteLine(gps.CallNumber());

            Console.WriteLine(gps.SendMessage());

            DecoratorBlueTooth bluetooth = new DecoratorBlueTooth(gps); //add GSP and bluetooth

            Console.WriteLine(bluetooth.CallNumber());

            Console.WriteLine(bluetooth.SendMessage());

            Console.Read();

     }

 

参考文章：http://www.cnblogs.com/kid-li/archive/2006/06/26/435966.html