I have been talking to the CLR interop team recently about some ideas to make life easier for developers using PInvoke.  My hope is that with WinFx PInvoking out to the Win32 will be much more rare, but we have a while to go before we get there.  In the meantime, we'd like your feedback:

Several times in the past, we’ve got feedback that it’s hard to write pinvoke declarations. We were asked to either provide a tool that would take an unmanaged C header file and produce pinvoke declarations in C# and/or VB.NET or to publish pinvoke declarations for the Win32 APIs. The first ask is unfortunately impossible to do 100% correctly since unmanaged header files are too ambiguous to be automatically convertible. For example, how would such tool convert char* parameter? As String, StringBuilder, ref char or char[]? It’s hard to know unless you read docs for that win32 function. The second ask was technically possible of course but we would always run into issue of resources and benefits i.e. is it really worth doing?

Currently, we are investigating variation of the second solution, which is publishing all pinvoke declarations we have in our code base in some searchable form (both C# and VB.NET variations). We are also planning to possibly allow community to post their own pinvoke declarations and grow database of declarations over time.

We are interested to know if this would be useful. Even though we couldn’t publish all the Win32 API declarations (or any other 3rd party API declarations) we hope that a) there would be reasonable chance you could find declarations you need, b) you would be able to use the database to learn how to write your own declarations, and c) you would be able to submit missing declarations and help other developers.

Please let us know if you have any feedback about this. Is this indeed an issue for you? Would such database help or even solve your issues with writing pinvoke declarations?