.NET单一代理与多播代理 [英] .NET single vs. multicast delegates

问题描述

我已经深入阅读了一些有关委托的内容，令人困惑的是，使用一种方法的委托可能与多播委托不同.但是，通过反射，您可以清楚地看到，即使仅使用一种方法，委托确实是从 MulticastDelegate 派生的，而不是立即从 Delegate 对象.

I have been reading a bit about delegates in depth, it is confusing that a delegate with one method could be different than a multicast delegate. However, via reflection, you can see plainly that even with only a single method, a delegate is indeed deriving from MulticastDelegate, and not immediately deriving from a Delegate object.

class Program 
{
    public delegate void MyDelegate();

    static void SomeMethod()
    {
    }

    static void Main(string[] args)
    {
        MyDelegate del = null;
        del = new MyDelegate(SomeMethod);
        Console.WriteLine(del.GetType().BaseType.Name);            
        Console.ReadKey();
    }
}

输出: MulticastDelegate

我意识到 MulticastDelegate 包含 Delegate 对象的调用列表.我想知道是否有可能直接创建单个 Delegate ，并且这样做是否有好处，除了调用 GetInvocationList()并提取单独委托对象.

I realize that a MulticastDelegate contains an invocation list of Delegate objects. I am wondering if it is possible to create a single Delegate directly and if there would be any advantage to doing so, other than calling GetInvocationList() and extracting the Delegate objects individually.

推荐答案

不是.所有.NET委托均来自 MulticastDelegate .最初编写.NET时，单"和."之间是有区别的.多播，但该区别在发布之前已被删除.但是，基础类型没有合并为一个.

Not really. All .NET delegates are derived from MulticastDelegate. When .NET was first written, there was originally a difference between single & multicast, but that distinction was dropped before release. However, the underlying types weren't merged into one.

您不能直接在C#中从 Delegate 派生.您也许可以使用原始IL，但是没有什么真正的意义，因为 MulticastDelegate 的运行方式像单播委托，可以实现所有意图和目的.

You can't derive from Delegate directly in C#. You might be able to in raw IL, but there's not really much point, as a MulticastDelegate operates like a singlecast delegate to all intents and purposes.

这篇关于.NET单一代理与多播代理的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！