Die-variants/event-example/die.cs - The die class with history and dieNotifier.

Lecture 5 - slide 40 : 45 Program 1

using System;
using System.Collections.Generic;

public class Die {
  public delegate void Notifier(string message);  // A delegate type

  private int numberOfEyes;
  private Random randomNumberSupplier; 
  private int maxNumberOfEyes;
  private List<int> history;
  public event Notifier twoSixesInARow;       

  public int NumberOfEyes{
     get {return numberOfEyes;}
  }

  public Die (): this(6){}

  public Die (int maxNumberOfEyes){
    randomNumberSupplier = new Random(unchecked((int)DateTime.Now.Ticks));
    this.maxNumberOfEyes = maxNumberOfEyes;
    numberOfEyes = randomNumberSupplier.Next(1, maxNumberOfEyes + 1);
    history = new List<int>();
    history.Add(numberOfEyes);
  }
    
  public void Toss (){
    numberOfEyes = randomNumberSupplier.Next(1,maxNumberOfEyes + 1);
    history.Add(numberOfEyes);
    if (DoWeHaveTwoSixesInARow(history))
       twoSixesInARow("Two sixes in a row");
  }

  private bool DoWeHaveTwoSixesInARow(List<int> history){
    int histLength = history.Count;
    return histLength >= 2 && 
           history[histLength-1] == 6 && 
           history[histLength-2] == 6;
  }
       
  public override String ToString(){
    return String.Format("Die[{0}]: {1}", maxNumberOfEyes, NumberOfEyes);
  }
}