背景：自定义控件的消息传递和方法的调用可以使用聚合器来进行

定义聚合器：

public class EventAggregator
{public static ConcurrentDictionary<Type, List<Action<object>>> _handles = new ConcurrentDictionary<Type, List<Action<object>>>();// 订阅方法public void Register<T> (Action<object> action){if (!_handles.ContainsKey(typeof (T))){_handles[typeof (T)] = new List<Action<object>> ();}_handles[typeof(T)].Add(action);Debug.WriteLine(_handles[typeof(T)].Count);}// 给数据给调用的方法public void Send<T> (object obj){if (_handles.ContainsKey(typeof(T))){foreach (var actionin in _handles[typeof(T)]){actionin?.Invoke(obj);}}}}

使用单例模式访问聚合器：

public class EventAggregatorRepository
{public EventAggregator eventAggregator;private static EventAggregatorRepository aggregatorRepository;private static object _lock = new object();public EventAggregatorRepository(){eventAggregator = new EventAggregator();}// 单例，只要一个事件聚合器public static EventAggregatorRepository GetInstance(){if (aggregatorRepository == null){lock (_lock){if (aggregatorRepository == null){aggregatorRepository = new EventAggregatorRepository();}}}return aggregatorRepository;}}

在发送消息的控件中：

public SendMsgControlViewModel()
{SendMsgCommand = new RelayCommand<Student>(SendMsg);
}private void SendMsg(object t)
{Student student = new Student(){Name = "梨花",Id = 12,};EventAggregatorRepository.GetInstance().eventAggregator.Send<Student>(student);
}

接收消息的控件中

public MainWindowViewModel()
{EventAggregatorRepository.GetInstance().eventAggregator.Register<Student>(ShowData);
}private void ShowData(object obj)
{Student student = (Student)obj;Receive = student.Name;  // 需要显示的属性绑定MessageBox.Show(Receive);
}

相关：WPF中MVVM手动实现PropertyChanged和RelayCommand-CSDN博客