>I don't know if what I'm about to ask is even possible because of how the people at Microsoft are protective of their source code but here goes:
>
>I would like to see the source code of some of the major controls in VFP (especially the OptionGroup control). Is it possible? Where, on my computer, can I find the class containing those items? If I can't see the source code from VFP for some reason, is there a whitepaper on the subject somewhere on the Web?
>
>Thanks in advance, Stephane.

You're not going to get it. It's considered intellectual property by Microsoft and is protected by copyright laws.