C＃ - 我怎么能和QUOT;超载＆QUOT;委托？ [英] C# - How can I "overload" a delegate?

问题描述

首先，我读了一些论坛和MSDN的帮助和所有说的委托，不能超载。

First, I was reading some forums and the help in MSDN and all says that a delegate can't be overloaded.

现在，我想有这样的事情：

Now, I want to have something like this:

public delegate void OneDelegate();
public delegate void OneDelegate(params object[] a);

public void DoNothing(params object[] a) {}
public void DoSomething() { /* do something */ }

private OneDelegate someFunction;

someFunction = new OneDelegate(DoSomething);
someFunction = new OneDelegate(DoNothing);

所以，就像你知道，你不能这样做，因为OneDelegate仅指第一个，而不是第二个。但是，有没有这样做的方法吗？或者类似的东西？

So, like you know, you CAN'T do this, because OneDelegate only refers to the first one and not the second one. But, is there a way for doing this? or something like that?

PS1：我wan't有任何数量的OneDelegate声明的，不只是一个或两个结果。
PS2：对不起，我英文不好

PS1: I wan't to have any number of OneDelegate declarations, not just one or two.
PS2: Sorry for my bad English.

推荐答案

设想一下，这是可能的。想我可以有一个重载的代表：

Imagine for a moment this was possible. Suppose I could have an overloaded delegate:

public delegate void OneDelegate(int i);
public delegate void OneDelegate(string s);

现在想象我宣布这个类型的变量，然后分配给它的功能，例如：

Now imagine I declare a variable of this type and then assign a function to it, for example:

OneDelegate myDelegate = StringMethod;

其中， StringMethod 的正是如此宣称：

public void StringMethod(string s) { Console.WriteLine(s); }

现在你通过 myDelegate 其他一些code，而code做到这一点：

Now you pass myDelegate to some other code, and that code does this:

myDelegate(47);

你有什么期望在这种情况下发生？怎样才能运行调用 StringMethod（）与整数参数？

如果你真的想要一个代表，可以采取的任何一组参数，在所有的，那么唯一的选择是有一个具有 params对象[] 数组：

If you really want a delegate that can take any set of parameters at all, then the only option is to have one with a params object[] array:

public delegate void OneDelegate(params object[] parameters);

但你必须分配给它，实际上可以处理任何对象数组的函数，例如：

But then you will have to assign to it a function that can actually handle any object array, for example:

public void MyMethod(params object[] parameters)
{
    if (parameters == null || parameters.Length == 0)
        throw new ArgumentException("No parameters specified.");
    if (parameters.Length > 1)
        throw new ArgumentException("Too many parameters specified.");

    if (parameters[0] is int)
        IntMethod((int) parameters[0]);
    else if (parameters[0] is string)
        StringMethod((string) parameters[0]);
    else
        throw new ArgumentException("Unsupported parameter type.");
}

如你所见，这变得混乱真正的快。因此，我向你，如果你需要这样一个代表，你可能已经在某个地方你的建筑设计犯了一个错误。确定这一缺陷，你着手实施之前，否则你的code的可维护性将遭受修复设计。

As you can see, this gets messy real quick. Therefore, I submit to you that if you need such a delegate, you have probably made a mistake somewhere in your architectural design. Identify this flaw and fix the design before you proceed with the implementation, as otherwise the maintainability of your code will suffer.

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