GuanChaZheTest/ConsoleApp1/Program.cs

using ConsoleApp;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
//using static ConsoleApp1.guanchazhe_jieko;

namespace ConsoleApp1
{
    // 使用观察者模式的示例
    //public class Program
    //{
    //    public static void Main(string[] args)
    //    {
    //        ISubject subject = new ConcreteSubject();

    //        IObserver observer1 = new ConcreteObserver("Observer 1");
    //        IObserver observer2 = new ConcreteObserver("Observer 2");

    //        subject.RegisterObserver(observer1);
    //        subject.RegisterObserver(observer2);

    //        subject.SetState("New state");
    //        subject.NotifyObservers();
    //    }
    //}
    class Program
    {
        static void Main(string[] args)
        {
            // 创建主题对象
            Subject subject = new Subject();

            // 创建观察者对象
            ConcreteObserverA observerA = new ConcreteObserverA();
            ConcreteObserverB observerB = new ConcreteObserverB();

            // 注册观察者
            subject.RegisterObserver(observerA);
            subject.RegisterObserver(observerB);

            // 改变状态并通知观察者
            subject.SetState("New State 1");
            subject.SetState("New State 2");

            // 注销观察者（可选）
            subject.UnregisterObserver(observerA);

            // 再次改变状态，只通知剩余的观察者
            subject.SetState("New State 3");
        }
    }
}