Upgrade existing VB6 COM component
Posted on 2010-08-15
I need to change an existing in-process COM DLL used by multiple visual basic applications. The COM DLL was written in Visual Basic 6 nearly 10 years ago by some consultants and the code was never provided or is no longer available. The problem is that the code has hard coded values that need to be changed.
The functionality of the code can easily be reproduced. So the question is what is the best way to create a replacement component? It would be ideal not to require that all the existing application be changed or recompiled to use the new component.
I was thinking of recreating the component in visual basic 6 and setting it to be binary compatible with the existing component. In that way it should be able to be deployed without affecting existing applications. But I have a longer term goal to migrate the entire application to .NET and this functionality would need to be migrated at some point.
I briefly looked at the Microsoft website for guidance and saw the recommendation to upgrade using COM interop. But can that be made binary compatible with the existing component?
Thanks for you advise and help!