Managed event, unmanaged sink

  • Thread starter Thread starter MLM450
  • Start date Start date
M

MLM450

I have created a .NET component in C# that has 2 interfaces. One is an
incoming interface with methods being exposed to COM-aware clients. The
other is an outgoing event interface that the unmanaged C++ sink
implements. Here is the C# code:

using System;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;
using System.Reflection;
using System.Diagnostics;

// Outgoing events
[InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]
public interface IEvents
{
void OnMyEvent(int MyCode);

}

// Incoming methods
public interface INotify
{
int Code { get; set; }
}

public delegate void MyDelegate(int nCode);

// Notify class
[ComSourceInterfaces("IEvents")]
[ClassInterface(ClassInterfaceType.None)]
public class Notify : INotify
{
private int m_Code = 5;

public event MyDelegate OnMyEvent;

public Notify()
{
}

public int Code
{
get { return m_Code; }
set
{
m_Code = value;
if (value >= 10)
{
try
{
if (null != OnMyEvent)
{
OnMyEvent(m_Code);
}
}
catch (Exception ex)
{
Trace.WriteLine(ex.Message);
}

}
}
}
}

In my unmanaged C++ client, I can access the INotify interface just
fine. But I want to access the event interface too. How do I do that?

Currently, I define the C++ pointer as:
ClassLibrary1::INotifyPtr pNotify;

And then my C++ class constructor's initializer has:
pNotify(__uuidof(ClassLibrary1::Notify))

Any suggestions would be appreciated.
Thanks!
 
public delegate void MyDelegate(int nCode);

// Notify class
[ComSourceInterfaces("IEvents")]
[ClassInterface(ClassInterfaceType.None)]
public class Notify : INotify [...]

In my unmanaged C++ client, I can access the INotify interface just
fine. But I want to access the event interface too. How do I do that?
Click to expand...
I've never done that. But typically, events are implemented with
connection points. You QI for the IConnectionPointContainer
and find the connection point for the event interface. You
can establish a connection to your implementation of the event
interface via Advise.

However, implementing dispinterfaces is a bit of a pain in
VC++. Unless you have any hard reason to do so, you
should not us InterfaceIsIDispatch (if you really want
late-binding you can still use a dual interface).

Anyway, you might want to use ATL to implement the
interface. See AtlAdvise and BEGIN_SINK_MAP.

-hg
 
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