C# 结束 BeginInvoke 的正确方法？

The proper way to end a BeginInvoke?

提问by Mike_G

I recently read this thread on MSDN. So I was thinking of using a lambda expression as a way of calling EndInvoke just as a way to make sure everything is nice and tidy. Which would be more correct?

我最近在 MSDN 上阅读了这个线程。所以我在考虑使用 lambda 表达式作为调用 EndInvoke 的一种方式，以确保一切都井井有条。哪个更正确？

example 1:

示例 1：

Action<int> method = DoSomething;

method.BeginInvoke(5, (a)=>{method.EndInvoke(a);}, null);

Example 2:

示例 2：

Action<int> method = DoSomething;

method.BeginInvoke(5, (a)=>
                                  {
                                      Action<int> m = a.AsyncState as Action<int>;
                                      m.EndInvoke(a);
                                  }, method);

采纳答案by Hans Passant

Your 2nd example is slightly more efficient because the "method" delegate instance doesn't have to be captured in the closure. I doubt you'd ever notice.

您的第二个示例效率更高，因为不必在闭包中捕获“方法”委托实例。我怀疑你从来没有注意到。

回答by Boris Callens

You might want to read thisthread on Haacked's blog. Haven't had a chance to test it, but the gist is in one of the last lines:

您可能想在 Haacked 的博客上阅读此主题。还没有机会测试它，但要点在最后一行之一：

ThreadPool.QueueUserWorkItem(callback => im.Send(to, from, subject, body));

回答by Marcelo Cantos

I don't know if this was possible way back in Jan '09, but certainly now you can just write this:

我不知道这在 09 年 1 月是否可行，但现在你可以这样写：

method.BeginInvoke(5, method.EndInvoke, null);