/// <summary>
 /// 电视机，提供抽象方法
 /// </summary>
 public abstract class TV
 {
  public abstract void On();
  public abstract void Off();
  public abstract void tuneChannel();
 }

 /// <summary>
 /// 三星牌电视机，重写基类的抽象方法
 /// </summary>
 public class Samsung:TV
 {
  public override void On()
  {
   Console.WriteLine("三星牌电视机已经打开了");
  }

  public override void Off()
  {
   Console.WriteLine("三星牌电视机已经关掉了");
  }

  public override void tuneChannel()
  {
   Console.WriteLine("三星牌电视机换频道");
  }
 }

 /// <summary>
 /// 长虹牌电视机，重写基类的抽象方法
 /// 提供具体的实现
 /// </summary>
 public class ChangHong : TV
 {
  public override void On()
  {
   Console.WriteLine("长虹牌电视机已经打开了");
  }

  public override void Off()
  {
   Console.WriteLine("长虹牌电视机已经关掉了");
  }

  public override void tuneChannel()
  {
   Console.WriteLine("长虹牌电视机换频道");
  }
 }

 /// <summary>
 /// 抽象概念中的遥控器，扮演抽象化角色
 /// </summary>
 public abstract class RemoteControl
 {
  public TV implementor { get; set; }

  /// <summary>
  /// 开电视机
  /// 这里抽象类中不再提供实现了，而是调用实现类中的实现
  /// </summary>
  public virtual void On()
  {
   implementor.On();
  }

  /// <summary>
  /// 关电视机
  /// </summary>
  public virtual void Off()
  {
   implementor.Off();
  }

  /// <summary>
  /// 换频道
  /// </summary>
  public virtual void SetChannel()
  {
   implementor.tuneChannel();
  }
 }

 /// <summary>
 /// 具体遥控器类
 /// </summary>
 public class ConcreteRemote:RemoteControl
 {
  /// <summary>
  /// 重写更换频道方法
  /// </summary>
  public override void SetChannel()
  {
   Console.WriteLine("重写更换频道方法");
   base.SetChannel();
  }
 }

static void Main(string[] args)
  {
   // 创建一个遥控器
   RemoteControl remoteControl = new ConcreteRemote();
   
   //长虹电视机
   remoteControl.implementor = new ChangHong();
   remoteControl.On();
   remoteControl.SetChannel();
   remoteControl.Off();
   Console.WriteLine();

   // 三星牌电视机
   remoteControl.implementor = new Samsung();
   remoteControl.On();
   remoteControl.SetChannel();
   remoteControl.Off();
   Console.Read();
  }