从C ++ / CLI挂钩C＃事件 [英] Hooking a C# event from C++/CLI

问题描述

所以我有一个C＃类，有以下事件：

  public class CSClient 
 {
 public delegate void OnMessageHandler（Object sender，EventArgs e）; 
 public event OnMessageHandler OnOptionsEvent; 
} 
  

然后我有一个C ++ / CLI类，我想订阅OnOptionsEvent。

我试过这样的：

  void CSClientWrapper :: Start（）
 {
 GCHandle h = GCHandle :: FromIntPtr（IntPtr（_impl））; 
 CSClient ^ obj = safe_cast< CSClient ^>（h.Target）; 
 
 __hook（& CSClient :: OnOptionsEvent，obj，& CSClientWrapper :: OnOptions）; 
} 
 
 void CSClientWrapper :: OnOptions（Object ^ sender，EventArgs ^ args）
 {
} 
  pre> 
 
 
 
 
错误C2039：'add_OnOptionsEvent'：不是'CSClient'的成员
 
 
 
错误C2750：'CSClient :: OnMessageHandler'：不能在
引用类型上使用'new'使用'gcnew'代替
 
 
我完全是新的C ++ CLI，所以我怀疑这是一个真正的根本缺少。
解决方案
是的，这不是合适的语法。最好忘记__hook关键字存在，这是一个相当错误的想法添加事件处理语法到本机C + +。您需要创建一个托管代理来订阅该事件，正确的语法应该接近：
  CSClient ^ obj = safe_cast< CSClient （h.Target）; 
 obj-> OnOptionsEvent + = 
 gcnew CSClient :: OnMessageHandler（this，& CSClientWrapper :: OnOptions）; 
  
 
So I have a C# class that has the following event:
public class CSClient
{
   public delegate void OnMessageHandler(Object sender, EventArgs e);
   public event OnMessageHandler OnOptionsEvent;
}
Then I have a C++/CLI class, for which I want to subscribe to OnOptionsEvent.

I have tried something like this:
void CSClientWrapper::Start()
{
   GCHandle h = GCHandle::FromIntPtr(IntPtr(_impl));
   CSClient^ obj = safe_cast<CSClient^>(h.Target);

   __hook(&CSClient::OnOptionsEvent, obj, &CSClientWrapper::OnOptions);
}

void CSClientWrapper::OnOptions(Object^ sender, EventArgs^ args)
{
}



  
error C2039: 'add_OnOptionsEvent' : is not a member of 'CSClient'
  
  
error C2750: 'CSClient::OnMessageHandler' : cannot use 'new' on the
  reference type; use 'gcnew' instead
I am completely new to C++CLI, so I suspect it is something really fundamental that I'm missing.
解决方案
Yes, that's not appropriate syntax.  Best to forget that the __hook keyword exists, it was a fairly mistaken idea to add event handling syntax to native C++.  You need to create a managed delegate to subscribe the event, correct syntax should be close to:
   CSClient^ obj = safe_cast<CSClient^>(h.Target);
   obj->OnOptionsEvent += 
      gcnew CSClient::OnMessageHandler(this, &CSClientWrapper::OnOptions);


                        
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