design-patterns - 耦合度太高-如何更好地设计此类？

Question

在我的代码上运行FxCop，我得到以下警告:

Microsoft.Maintainability : 'FooBar.ctor is coupled with 99 different types from 9 different namespaces. Rewrite or refactor the method to decrease its class coupling, or consider moving the method to one of the other types it is tightly coupled with. A class coupling above 40 indicates poor maintainability, a class coupling between 40 and 30 indicates moderate maintainability, and a class coupling below 30 indicates good maintainability.

我的类(class)是所有来自服务器的消息的登陆区。服务器可以向我们发送不同EventArgs类型的消息:

public FooBar()
{
    var messageHandlers = new Dictionary<Type, Action<EventArgs>>();
    messageHandlers.Add(typeof(YouHaveBeenLoggedOutEventArgs), HandleSignOut);
    messageHandlers.Add(typeof(TestConnectionEventArgs), HandleConnectionTest);
    // ... etc for 90 other types
}

“HandleSignOut”和“HandleConnectionTest”方法中几乎没有代码。他们通常将工作传递给另一个类中的函数。

如何在降低耦合的情况下使此类更好？

Answer 1

让负责工作的类(class)注册他们感兴趣的事件... event broker模式。

class EventBroker {
   private Dictionary<Type, Action<EventArgs>> messageHandlers;

   void Register<T>(Action<EventArgs> subscriber) where T:EventArgs {
      // may have to combine delegates if more than 1 listener
      messageHandlers[typeof(T)] = subscriber; 
   }

   void Send<T>(T e) where T:EventArgs {
      var d = messageHandlers[typeof(T)];
      if (d != null) {
         d(e);
      }
   }
}