How to create a simple COM component in C++

Question

How to create a simple COM component in C++, and then to consume it in my C# project.

I don't want to use ATL. Are there any simple step by step instructions or a complete procedure to get started. (I have done googling but not found any desired content).

Any help will be appreciated.

Answer 1

1. empty DLL project
2. exports from the DLL to be used by COM: DllGetClassObject and friends
3. implementation of COM object factory
4. implementation of the COM object itself
5. type library is recommended to be embedded for better integration with C#
6. COM object registration

All steps assume understanding of COM basics, of course. ATL covers most of this right from the start, a project created from template is taking you immediately to details of #4 above.

If you are looking for some sample to start from, you can find pretty close ones:

• COM in C++
• Writing a shell extension in plain C++