/// <summary>
  /// 手机抽象类,即抽象者模式中的抽象组件类
  /// </summary>
  public abstract class Phone
  {
    /// <summary>
    /// 打印方法
    /// </summary>
    public abstract void Print();
  }

  /// <summary>
  /// 苹果手机，即装饰着模式中的具体组件类
  /// </summary>
  public class ApplePhone:Phone
  {
    /// <summary>
    /// 重写基类的方法
    /// </summary>
    public override void Print()
    {
      Console.WriteLine("我有一部苹果手机");
    }
  }

  /// <summary>
  /// 装饰抽象类，让装饰完全取代抽象组件，所以必须继承Phone
  /// </summary>
  public abstract class Decorator:Phone
  {
    private Phone p ;  //该装饰对象装饰到的Phone组件实体对象
    
    public Decorator(Phone p)
    {
      this.p = p;
    }

    public override void Print()
    {
      if (this.p != null)
      {
        p.Print();
      }
    }
  }

  /// <summary>
  /// 贴膜，具体装饰者
  /// </summary>
  public class Sticker:Decorator
  {
    public Sticker(Phone p) : base(p) { }

    public override void Print()
    {
      base.Print();
      //添加行为
      AddSticker();
    }

    /// <summary>
    /// 新的行为方法
    /// </summary>
    public void AddSticker()
    {
      Console.WriteLine("现在苹果手机有贴膜了");
    }
  }

  /// <summary>
  /// 手机挂件，即具体装饰者
  /// </summary>
  public class Accessories:Decorator
  {
    public Accessories(Phone p) : base(p) { }

    public override void Print()
    {
      base.Print();

      // 添加新的行为
      AddAccessories();
    }

    /// <summary>
    /// 新的行为方法
    /// </summary>
    public void AddAccessories()
    {
      Console.WriteLine("现在苹果手机有漂亮的挂件了");
    }
  }

  /// <summary>
  /// 设计模式-装饰者模式
  /// </summary>
  class Program
  {
    static void Main(string[] args)
    {
      Phone ap = new ApplePhone(); //新买了个苹果手机
      Decorator aps = new Sticker(ap); //准备贴膜组件
      aps.Print();

      Decorator apa = new Accessories(ap); //过了几天新增了挂件组件
      apa.Print();

      Sticker s = new Sticker(ap);    //准备贴膜组件
      Accessories a = new Accessories(s);//同时准备挂件
      a.Print(); 
    }
  }