using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;namespace WpfLibraryEventAggregator
{public class EventAggregator{/// <summary>/// 定义数据暂存/// </summary>private readonly Dictionary<Type, List<Delegate>> _handlers = new Dictionary<Type, List<Delegate>>();// 订阅事件, 订阅后后续被触发事件 /// <summary>/// d订阅事件 泛型方法/// </summary>/// <typeparam name="TEvent"></typeparam>/// <param name="handler"></param>public void Subscribe<T>(Action<T> handler){Type eventType = typeof(T); if (!_handlers.ContainsKey(eventType)){_handlers[eventType] = new List<Delegate>();}_handlers[eventType].Add(handler);}// 取消订阅事件 /// <summary>/// 取消订阅事件 /// </summary>/// <typeparam name="TEvent"></typeparam>/// <param name="handler"></param>public void Unsubscribe<T>(Action<T> handler){Type eventType = typeof(T);if (_handlers.ContainsKey(eventType)){_handlers[eventType].Remove(handler);// 如果该事件类型没有订阅者了，可以移除它（可选） if (!_handlers[eventType].Any()){_handlers.Remove(eventType);}}}/// <summary>/// // 发布事件 /// </summary>/// <typeparam name="T"></typeparam>/// <param name="eventToPublish"></param>public void Publish<T>(T eventToPublish){Type eventType = typeof(T);if (_handlers.ContainsKey(eventType)){foreach (var handler in _handlers[eventType].ToList()) // 使用 ToList 以避免在迭代时修改集合 {((Action<T>)handler)(eventToPublish);}}}}
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using WpfLibraryEventAggregator;namespace WpfApp1.eventAggregator
{/// <summary>/// 自定义定义事件类/// </summary>public class MessageEvent //: EventArgs{public string Message { get; }public MessageEvent(string message){Message = message;}}}
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using WpfApp1.eventAggregator;
using WpfLibraryEventAggregator;namespace WpfApp1
{/// <summary>/// Interaction logic for MainWindow.xaml/// </summary>public partial class MainWindow : Window{private readonly EventAggregator _eventAggregator = new EventAggregator();public MainWindow(){InitializeComponent();// 订阅事件 _eventAggregator.Subscribe<MessageEvent>(OnMessageReceived);}/// <summary>/// 可以在别的页面调用来触发该事件相应/// </summary>/// <param name="e"></param>private void OnMessageReceived(MessageEvent e){// 处理事件，例如更新 UI MessageBox.Show(e.Message);}private void btnevent_Click(object sender, RoutedEventArgs e){// 假设在某个地方发布事件 ，发布会触发本页面_eventAggregator.Publish(new MessageEvent("Hello, WPF!"));}// 确保在窗口关闭时取消订阅（可选） protected override void OnClosed(EventArgs e){// 注意：在这个简单的例子中，我们并没有真正的取消订阅逻辑， // 因为 MainWindow 的实例将在应用程序结束时被销毁。 // 在更复杂的应用程序中，你可能需要跟踪所有订阅并显式取消它们。 _eventAggregator.Unsubscribe<MessageEvent>(OnMessageReceived);// 避免事件挤压base.OnClosed(e);}}
}
