using System; using System.Collections.Generic;namespace ConsoleApplication10 {/// <summary>/// 在軟件構建過程中，我們需要為某些對象建立一種“通知依賴關系” /// ——一個對象（目標對象）的狀態發生改變，所有的依賴對象（觀察者對象）都將得到通知。/// 如果這樣的依賴關系過于緊密，將使軟件不能很好地抵御變化。使用面向對象技術，可以將這種依賴關系弱化，/// 并形成一種穩定的依賴關系。從而實現軟件體系結構的松耦合。/// </summary>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();}}/// <summary>/// 股票/// </summary>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;}/// <summary>/// 發送信息/// </summary>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; }}}/// <summary>/// 微軟的股票/// </summary>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);}}} using System; using System.Collections.Generic;namespace ConsoleApplication10 {/// <summary>/// 在軟件構建過程中，我們需要為某些對象建立一種“通知依賴關系” /// ——一個對象（目標對象）的狀態發生改變，所有的依賴對象（觀察者對象）都將得到通知。/// 如果這樣的依賴關系過于緊密，將使軟件不能很好地抵御變化。使用面向對象技術，可以將這種依賴關系弱化，/// 并形成一種穩定的依賴關系。從而實現軟件體系結構的松耦合。/// </summary>class Program{static void Main(string[] args){Stock stock = new Stock("Microsoft", 120.00);Investor investor = new Investor("Jom");Investor investor1 = new Investor("Sam");stock.NotifyEvent += new NotifyEventHandler(investor.SendData);stock.NotifyEvent += new NotifyEventHandler(investor1.SendData);stock.Update();Console.ReadLine();}}public delegate void NotifyEventHandler(object sender);public class Stock{public NotifyEventHandler NotifyEvent;private String _symbol;private double _price;public Stock(String symbol, double price){this._symbol = symbol;this._price = price;}public void Update(){OnNotifyChange();}public void OnNotifyChange(){if (NotifyEvent != null){NotifyEvent(this);}}public String Symbol{get { return _symbol; }}public double Price{get { return _price; }}}public class Investor{private string _name;public Investor(string name){this._name = name;}public void SendData(object obj){if (obj is Stock){Stock stock = (Stock)obj;Console.WriteLine("Notified {0} of {1}'s " + "change to {2:C}", _name, stock.Symbol, stock.Price);}}} }

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轉載于:https://www.cnblogs.com/lgxlsm/p/4647067.html

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