I am writing a file manager (in C#) which uses a dll which hooks into
the system sending my app a message when a window is created or
destroyed, the dll works fine and I am receiving the messages.
When I receive a Window Created message I want to get a handle on its
icon and use it as a graphic on a button (which allows switching to
that application).
Everything is working except getting a handle on an icon for any app I
have written in C#. If any program is started I can pick up its icon
as follows:

ipHIcon = GetClassLong(ipWindow, GCL_HICON);

if(ipHIcon != IntPtr.Zero)
{
    System.Drawing.Icon SIcon= Icon.FromHandle(ipHIcon);
    imlApps.Images.Add(SIcon);
    jraTemp.intIconIndex = imlApps.Images.Count - 1;
    // Clean up - must be done after image inserted in to image list
    jff.JDestroyIcon(ipHIcon);
}
else
    jraTemp.intIconIndex = 0;

I always end up with 0 as my iconindex for any of my own apps written
in C# which seems to imply that GetClassLong won't work for .Net
framework apps. I can get the icon handle I want on my own apps
written in Delphi for instance.

I have tried re-compiling with the app icon as Content, Compile and
Embedded Resource but it makes no difference.

Can anybody advise me how to get a valid icon handle for an app
compiled to run under the .Net framework please?