HOWTO: Combine Managed and Unmanaged Projects into a Single Visual Studio Solution

// The following ifdef block is the standard way of creating macros which make exporting 
// from a DLL simpler. All files within this DLL are compiled with the UNMANAGED_EXPORTS
// symbol defined on the command line. this symbol should not be defined on any project
// that uses this DLL. This way any other project whose source files include this file see 
// UNMANAGED_API functions as being imported from a DLL, wheras this DLL sees symbols
// defined with this macro as being exported.
#ifdef UNMANAGED_EXPORTS
#define UNMANAGED_API __declspec(dllexport)
#else
#define UNMANAGED_API __declspec(dllimport)
#endif

// This class is exported from the Unmanaged.dll
class UNMANAGED_API CUnmanaged {
public:
	CUnmanaged(void);
	// TODO: add your methods here.
};

extern UNMANAGED_API int nUnmanaged;

#ifdef __cplusplus
extern "C"
{
#endif

UNMANAGED_API int fnUnmanaged(LPCTSTR lpszMessage);

#ifdef __cplusplus
} // extern "C"
#endif