I've just started delving into StackOverflow.com, and I think it's great! Good job all involved!

I know it's made by mr Coding Horror himself, so it always had a lot of promise, but it's easy to use, responsive, well thought out, and ADDICTIVE!

For those who don't know, it's basically the Yahoo Answers for programmers, except that it has extra addictive features, it's very fast and some of the answers that come out of it are just pure quality.

The idea of the 'badges' is great, makes you almost feel like you're in a game trying to score points, you earn a badge when you accomplish something, it's like being in a MMORPG but instead of killing 3000 lizards you're letting someone know how to write graceful REGEX patterns.

I suggest everyone check it out

Creating C# DLL's for use with COM is not too hard, however event exposure can be a little messy especially when trying to subscribe to events in vb6 or vba.

Here's an example of an everyday COM exposed class:

ComVisible(true)
ClassInterface(ClassInterfaceType.AutoDual)
public class CComInterop

We've integrated automatic interface generation so we don't have to make our own. However, this interface type does not expose events.

The solution is to create a separate interface to expose the events but no other properties / methods of the class. Using some jiggery pokery it is also possible to integrate the contents of this interface into the class itself so that you don't have to deal with multiple objects on the COM side.

METHOD:

this is our event, and the event's delegate:

public event SomeEventHandler SomeEvent;

public delegate void SomeEventHandler(string teststring);

To expose this event we create the following interface:

ComVisible(true)
InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIDispatch)
public interface IComInteropEvents
{
void SomeEvent(string teststring);
}

The important part is that we specify the interface type as IDispatch.

But we don't want to have to declare a separate object for events, so we add a 'ComSourceInterfacesAttribute' referencing this interface, like so:

ComVisible(true)
ComSourceInterfacesAttribute("Tam.Common.LzLibrary.IComInteropEvents")
ClassInterface(ClassInterfaceType.AutoDual)
public class CComInterop

Now we can use the object's events in vb6 or vba without having to declare separate objects!

Public WithEvents InteropObject As Some_Library.CComInterop

and you can still use the methods and properties of the object normally with all intellisense intact.

Full sample Class and interface shown below:

ComVisible(true)
InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIDispatch)
public interface IComInteropEvents
{
void SomeEvent(string teststring);
}

public delegate void SomeEventHandler(string teststring);

ComVisible(true)
ComSourceInterfacesAttribute("Tam.Common.LzLibrary.IComInteropEvents")
ClassInterface(ClassInterfaceType.AutoDual)
public class CComInterop
{
private int m_nSomeProperty = 0;
public event SomeEventHandler SomeEvent;

public void SomeMethod(int nValue)
{
m_nSomeProperty = nValue;
// Raises the event
SomeEvent("Hello");
}

public int SomeProperty
{
get { return m_nSomeProperty; }
set { m_nSomeProperty = value; }
}
}

Enjoy!