如何创建基于现有一个新的委托类型，在C＃中？ [英] How do I create a new delegate type based on an existing one, in C#?

问题描述

有没有办法，我可以创建基于现有一个新的委托类型的任何方式？就我而言，我想创建一个委托 MyMouseEventDelegate 这将具有相同的功能事件处理程序和LT; MouseEventArgs>

Is there any way that I can create a new delegate type based on an existing one? In my case, I'd like to create a delegate MyMouseEventDelegate which would have the same functionality as EventHandler<MouseEventArgs>.

为什么我要这样？趁编译时类型检查，当然！这样一来，我可以有两种不同的代表： MyRightClickHandler 和 MyLeftClickHandler ，两者永远不得混淆 - 即使他们都是功能上等同于事件处理程序和LT; MouseEventArgs方式>

Why do I want this? To take advantage of compile-time type-checking, of course! This way, I can have two different delegates: MyRightClickHandler and MyLeftClickHandler, and never the twain shall be confused - even if they are both functionally identical to EventHandler<MouseEventArgs>.

有没有语法，做这样的事情

Is there syntax to do this sort of thing?

哦，这样的代码：

using MyRightClickHandler = EventHandler<MouseEventArgs>

不够好。它不会做任何类型检查，因为它实际上并不创建新的类型。而且我必须贴上这样一行到每一个代码文件，在其中我要提到 MyRightClickHandler 。

推荐答案

嗯，这是因为复制从原来的委托声明一样简单。没有什么在C＃中自动执行此操作的，但我不能看到它的太大负担：

Well, it's as simple as copying the delegate declaration from the original. There's nothing in C# to do this automatically, but I can't see it's much of a burden:

public delegate void MyLeftClickHandler(object sender, MouseEventArgs e);
public delegate void MyRightClickHandler(object sender, MouseEventArgs e);

这不像 MouseEventHandler 将改变任何时间很快...

It's not like MouseEventHandler is going to change any time soon...

你有没有真正被因在错误的地方使用了错误的代表，虽然虫子咬伤？我不记得曾经有发现这个问题我自己，在我看来，你是引入更多的工作（和其他开发人员不熟悉的一套代表） - ？你肯定是值得的。

Have you actually been bitten by bugs due to using the wrong delegates in the wrong places though? I can't remember ever having found this a problem myself, and it seems to me you're introducing more work (and an unfamiliar set of delegates for other developers) - are you sure it's worth it?

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