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Marshal a C# struct to native C++

Posted By:      Posted Date: April 10, 2011    Points: 0   Category :WPF

Platform is WS 2008 RC2, VS 2010.

I have what I think should be a pretty straightforward marshalling situation, but it just isn't working as expected.

Native Code:

#pragma pack(push, 8)
struct Handle
unsigned long Type;
void* Value;
void* Owner;
#pragma pack(pop)

__declspec(dllexport) Handle __cdecl CreateStyleProvider(const wchar_t* provider);
__declspec(dllexport) Handle __cdecl CreateOutputGroup(long ordinal, Handle style);

The Handle struct is really just opaque data that gets passed around.

C# code:

[StructLayout(LayoutKind.Sequential, Pack=8)]

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