c# - passing an array of structs to a native DLL

[Azrael_666]

Hi all,

I've been looking for some assistance on this all day with no luck, so any pointers would be helpful.

struct SID_SEARCH_RESULT_DATA
{
ULONG ulFieldID;
USHORT usFieldLength;
char szFieldData[FIELD_LENGTH];
};

I want to pass this from a c# app into an unmanaged c++ dll and populate it. I've tried a couple of things but with no joy - can anyone give me an idea of the c++ exported method signature and the c# extern method declaration required to pass an array of this struct and populate it?

The main complication is that I won't know how many results I will have up front, so I need to be able to assign sufficient memory on the c++ dll side.

Any help would be hugely appreciated.

Thanks , Lee.

Edit: The C++ dll is not a COM object or anything similar, just a straight DLL. That's why I want to do this via p/invoke and some sort of marshalling wizardry. As you may be able to tell, this has landed on my desk with an urgent sticker on it and I'm new to c# & .NET, so I just need to get it working.