为事件定义一个空委托体是一个很好的做法吗？ [英] Is it a good practice to define an empty delegate body for a event?

问题描述

可能重复：

为事件定义一个空委托体是一个很好的做法，这样就不用担心引发没有事件处理程序的事件？ （不需要检查事件是否为空）

Is it a good practice to define an empty delegate body for a event so that you do not need to worry raise a event which have no event handler? ( no need to check whether event is null).

如下代码：

public event EventHandler<LoadEventArgs> LoadedData = delegate { };

推荐答案

我确实发现它很有用，是的。将会有一个微小的，微小的性能成本 - 但是不用执行无效测试的可读性的好处使它值得IMO。

I've certainly found it useful, yes. There will be a tiny, tiny performance cost - but the benefit in readability for not having to perform the nullity test makes it worth it IMO.

值得一提的是，是使用匿名方法而不是lambda表达式的好几次之一，否则您必须命名您将忽略的参数，如下所示：

It's worth pointing out that this is one of the few times when it's good to use an anonymous method rather than a lambda expression - otherwise you have to name the parameters that you're going to ignore, like this:

public event EventHandler<LoadEventArgs> LoadedData = (sender, args) => {};

我不喜欢命名我不打算使用的东西：）

I don't like having to name things I'm not intending to use :)

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