观察者模式

最新推荐文章于 2025-06-16 09:51:36 发布

weixin_34234823

最新推荐文章于 2025-06-16 09:51:36 发布

阅读量54

点赞数

CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/z2002m/archive/2008/08/04/1259790.html

Code
public abstract class Stock

{
    private List<IObserver> observers = new List<IObserver>();

    private String _symbol;

    private double _price;

    public Stock(String symbol, double price)

    {
        this._symbol = symbol;

        this._price = price;
    }

    public void Update()

    {
        foreach (IObserver ob in observers)

        {
            ob.SendData(this);
        }

    }

    public void AddObserver(IObserver observer)

    {
        observers.Add(observer);
    }

    public void RemoveObserver(IObserver observer)

    {
        observers.Remove(observer);
    }

    public String Symbol

    {
        get { return _symbol; }
    }

    public double Price

    {
        get { return _price; }
    }
}

public class Microsoft : Stock

{

    public Microsoft(String symbol, double price)

        : base(symbol, price)

    { }
}

public interface IObserver

{
    void SendData(Stock stock);
}

public class Investor : IObserver

{
    private string _name;

    public Investor(string name)

    {
        this._name = name;
    }

    public void SendData(Stock stock)

    {
        Console.WriteLine("Notified {0} of {1}'s " + "change to {2:C}", _name, stock.Symbol,stock.Price);

    }

}

客户端程序代码如下：

class Program

{
    static void Main(string[] args)

    {
        Stock ms = new Microsoft("Microsoft",120.00);

        ms.AddObserver(new Investor("Jom"));

        ms.AddObserver(new Investor("TerryLee"));

        ms.Update();

        Console.ReadLine();
    }

}

转载于:https://www.cnblogs.com/z2002m/archive/2008/08/04/1259790.html