它是安全的代表加入到与关键字新的事件？ [英] Is it safe to add delegates to events with keyword new?

问题描述

有一件事我所关心的是，我发现注册代表事件的两种方式。

One thing I am concerned with is that I discovered two ways of registering delegates to events.

1. OnStuff + = this.Handle;
2. OnStuff + =新StuffEventHandler（this.Handle）;

第一个是干净的，它是有道理的做OnStuff - = this.Handle;从事件注销...但与后者的情况下，应该怎么做OnStuff - =新StuffEventHandler（this.Handle）;？这感觉就像我没有删除任何东西，因为我扔在另一个StuffEventHandler参考。是否该事件作为参考比较的委托？我很担心，我可以在这里开始讨厌的内存池。给我？我没有提及新StuffEventHandler我previously注册。

The first one is clean, and it makes sense doing "OnStuff -= this.Handle;" to unregister from the event... But with the latter case, should I do "OnStuff -= new StuffEventHandler(this.Handle);"? It feels like I am not removing anything at all, since I'm throwing in another StuffEventHandler reference. Does the event compare the delegate by reference? I am concerned I could start a nasty memory pool here. Get me? I don't have the reference to the "new StuffEventHandler" I previously registered.

什么是这样做的缺点＃1？

What is the downside of doing #1?

什么是做＃2的好处？

What is benefit of doing #2?

推荐答案

您不必担心保持引用最初注册代​​理，你会不会开始一个讨厌的内存池。

You don't need to worry about keeping a reference to the originally registered delegate, and you will not start a "nasty memory pool".

当你调用OnStuff - =新StuffEventHandler（this.Handle）;去除code做的没有的比较，你通过引用删除委托：它检查是否相等比较参考目标方法（S），该​​委托将调用，并从删除匹配代表OnStuff。

When you call "OnStuff -= new StuffEventHandler(this.Handle);" the removal code does not compare the delegate you are removing by reference: it checks for equality by comparing references to the target method(s) that the delegate will call, and removes the matching delegates from "OnStuff".

顺便说一句，OnStuff本身就是一个委托对象（即我假设你已经在你的宣言事件关键字简单地限制了委托的访问）。

By the way, "OnStuff" itself is a delegate object (the event keyword that I assume you have in your declaration simply restricts the accessibility of the delegate).

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