在我的集線器類中訪問內部靜態集合

Question

我有一個集線器類，有一個「在線」用戶的靜態集合，我有另一個集線器類，我想能夠顯示第一個集線器的「在線」用戶我將如何去做到這一點，具體來說，我該如何讓2個集線器類互相交談並在它們之間共享數據（我的靜態集合）

Answer 1

簡單版本：讓第一類公開一個類event，另一個實現事件監聽器。

using System; 

namespace EventSample 
{ 
    // Class that contains the data for 
    // the alarm event. Derives from System.EventArgs. 
    // 
    public class AlarmEventArgs : EventArgs 
    { 
     private bool snoozePressed; 
     private int nrings; 

     //Constructor. 
     // 
     public AlarmEventArgs(bool snoozePressed, int nrings) 
     { 
      this.snoozePressed = snoozePressed; 
      this.nrings = nrings; 
     } 

     // The NumRings property returns the number of rings 
     // that the alarm clock has sounded when the alarm event 
     // is generated. 
     // 
     public int NumRings 
     { 
      get { return nrings;} 
     } 

     // The SnoozePressed property indicates whether the snooze 
     // button is pressed on the alarm when the alarm event is generated. 
     // 
     public bool SnoozePressed 
     { 
      get {return snoozePressed;} 
     } 

     // The AlarmText property that contains the wake-up message. 
     // 
     public string AlarmText 
     { 
      get 
      { 
       if (snoozePressed) 
       { 
        return ("Wake Up!!! Snooze time is over."); 
       } 
       else 
       { 
        return ("Wake Up!"); 
       } 
      } 
     } 
    } 

    // Delegate declaration. 
    // 
    public delegate void AlarmEventHandler(object sender, AlarmEventArgs e); 

    // The Alarm class that raises the alarm event. 
    // 
    public class AlarmClock 
    { 
     private bool snoozePressed = false; 
     private int nrings = 0; 
     private bool stop = false; 

     // The Stop property indicates whether the 
     // alarm should be turned off. 
     // 
     public bool Stop 
     { 
      get {return stop;} 
      set {stop = value;} 
     } 

     // The SnoozePressed property indicates whether the snooze 
     // button is pressed on the alarm when the alarm event is generated. 
     // 
     public bool SnoozePressed 
     { 
      get {return snoozePressed;} 
      set {snoozePressed = value;} 
     } 

     // The event member that is of type AlarmEventHandler. 
     // 
     public event AlarmEventHandler Alarm; 

     // The protected OnAlarm method raises the event by invoking 
     // the delegates. The sender is always this, the current instance 
     // of the class. 
     // 
     protected virtual void OnAlarm(AlarmEventArgs e) 
     { 
      AlarmEventHandler handler = Alarm; 
      if (handler != null) 
      { 
       // Invokes the delegates. 
       handler(this, e); 
      } 
     } 

     // This alarm clock does not have 
     // a user interface. 
     // To simulate the alarm mechanism it has a loop 
     // that raises the alarm event at every iteration 
     // with a time delay of 300 milliseconds, 
     // if snooze is not pressed. If snooze is pressed, 
     // the time delay is 1000 milliseconds. 
     // 
     public void Start() 
     { 
      for (;;) 
      { 
       nrings++; 
       if (stop) 
       { 
        break; 
       } 
       else 
       { 
        if (snoozePressed) 
        { 
         System.Threading.Thread.Sleep(1000); 
        } 
        else 
        { 
         System.Threading.Thread.Sleep(300); 
        } 
        AlarmEventArgs e = new AlarmEventArgs(snoozePressed, nrings); 
        OnAlarm(e); 
       } 
      } 
     } 
    } 

    // The WakeMeUp class has a method AlarmRang that handles the 
    // alarm event. 
    // 
    public class WakeMeUp 
    { 
     public void AlarmRang(object sender, AlarmEventArgs e) 
     { 
      Console.WriteLine(e.AlarmText +"\n"); 

      if (!(e.SnoozePressed)) 
      { 
       if (e.NumRings % 10 == 0) 
       { 
        Console.WriteLine(" Let alarm ring? Enter Y"); 
        Console.WriteLine(" Press Snooze? Enter N"); 
        Console.WriteLine(" Stop Alarm? Enter Q"); 
        String input = Console.ReadLine(); 

        if (input.Equals("Y") ||input.Equals("y")) 
        { 
         return; 
        } 
        else if (input.Equals("N") || input.Equals("n")) 
        { 
         ((AlarmClock)sender).SnoozePressed = true; 
         return; 
        } 
        else 
        { 
         ((AlarmClock)sender).Stop = true; 
         return; 
        } 
       } 
      } 
      else 
      { 
       Console.WriteLine(" Let alarm ring? Enter Y"); 
       Console.WriteLine(" Stop Alarm? Enter Q"); 
       String input = Console.ReadLine(); 
       if (input.Equals("Y") || input.Equals("y")) 
       { 
        return; 
       } 
       else 
       { 
        ((AlarmClock)sender).Stop = true; 
        return; 
       } 
      } 
     } 
    } 


    // The driver class that hooks up the event handling method of 
    // WakeMeUp to the alarm event of an Alarm object using a delegate. 
    // In a forms-based application, the driver class is the 
    // form. 
    // 
    public class AlarmDriver 
    { 
     public static void Main(string[] args) 
     { 
      // Instantiates the event receiver. 
      WakeMeUp w = new WakeMeUp(); 

      // Instantiates the event source. 
      AlarmClock clock = new AlarmClock(); 

      // Wires the AlarmRang method to the Alarm event. 
      clock.Alarm += new AlarmEventHandler(w.AlarmRang); 

      clock.Start(); 
     } 
    } 
} 

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