Using a conversion program from Tangible software it's possible to get a "partial" conversion of c++ files to C#.
The conversion is far from complete. The conversion program adds "warnings" and "todos" where it has problems with converting, but if one is just learning c++ and coming from a C# background, the side by side comparisons helps to see the similarity between the languages. That said, it's a heck of a lot better than hand coding the conversion even if you are a c++/C# pro. I am not recommending this as a substitute for a wrapper (as Pendra notes above). It's just to help with understanding for C++ virgins.
I've uploaded a conversion of R&D to a share site (it's from the google SVN and is from an now two week-ish old R&D commit-- all attributions to original writer intact). The moderators are of course welcome to take this link out if this kind of sharing is "inappropriate".
Converted.rar
HBNB