当我写我的业务对象的公共事件，我已经适应总是通过实例为发件人为对象中，除了额外的具体参数的习惯。刚才我问我自己现在的为什么我不能指定类？

When I write public events for my business objects, I've adapted the habit of always passing the instance as "sender as Object", in addition to additional specific parameters. I just asked myself now why am I not specifying the class?

因此​​，对于你有更多的经验; 你曾经通过不同的类，发件人在事件？如果是的话，什么是您的决策标准作为的时候，这是正常/不正常？

So for you with more experience; Do you ever pass the distinct class as sender in an event? And if so, what are your decision criteria for when this is ok/not ok?

推荐答案

不要偏激。 事件处理程序（对象发件人，EventArgs五）有一个对象发件人，使我们可以在许多情况下使用它。不过，这并不意味着一个强类型的发送者是邪恶的。强类型发件人是当这种委托是不会被广泛使用的有用（如事件处理程序）例如：

Don't be extreme. EventHandler(object sender, EventArgs e) has an object sender so that we can use it in many circumstances. But it doesn't mean a strongly-typed sender is evil. A strongly-typed sender is useful when this delegate is not going to be widely used(like EventHandler) e.g.

public delegate void SaveHandler(Controller sender, EventArgs e);

现在其他开发人员（或某人使用您的库）可以recogonize发送者的有无以的是控制器，他们会高兴不至code是这样的：

Now other developers(or someone using your library) can recogonize that the sender have to be a Controller, and they will be glad not to code like this:

public void MySaveHandler(object sender, EventArgs arg)
{
   var controller = sender as Controller;
   if (controller != null)
   {
       //do something
   }
   else
   {
       //throw an exception at runtime? 
       //It can be avoided if sender is strongly-typed
   }
}

和你甚至可以让通用的：

And you can even make it generic:

public delegate void SaveHandler<T>(T sender, EventArgs args) 
                                              where T: IController;

这是在C＃中的纯法律和好的做法。你应该清楚你想做什么，然后做出更好的选择。无论他们是邪恶的/坏的。

It's pure legal and good practice in C#. You should make clear what you want to do, and then choose the better way. Either of them is evil/bad.