Managed C++/CLI

class CLoadLibrary
{
public:
	CLoadLibrary(LPCTSTR lpszLibFileName);
	virtual ~CLoadLibrary();
	operator HINSTANCE();
	DWORD GetModuleVersion();

protected:
	HINSTANCE m_hLibModule;
};

CLoadLibrary::CLoadLibrary(LPCTSTR lpszLibFileName)
{
	m_hLibModule = ::LoadLibrary(lpszLibFileName);
	ASSERT(m_hLibModule != NULL);
}

CLoadLibrary::~CLoadLibrary()
{
	::FreeLibrary(m_hLibModule);
}

CLoadLibrary::operator HINSTANCE()
{
	return m_hLibModule; // cast operator
}

DWORD CLoadLibrary::GetModuleVersion()
{
	typedef HRESULT (CALLBACK* DLLGETVERSIONPROC)(DLLVERSIONINFO*);

	DLLGETVERSIONPROC pDllGetVersion =
		(DLLGETVERSIONPROC)::GetProcAddress(*this, _T("DllGetVersion"));

	DWORD dwVersion = 0L;
	if (pDllGetVersion != NULL)
	{
		DLLVERSIONINFO dvi;
		ZeroMemory(&dvi, sizeof(dvi));
		dvi.cbSize = sizeof(dvi);
		
		HRESULT hr = (*pDllGetVersion)(&dvi);
		if (SUCCEEDED(hr))
		{
			ASSERT(dvi.dwMajorVersion <= 0xFFFF);
			ASSERT(dvi.dwMinorVersion <= 0xFFFF);
			dwVersion = MAKELONG(dvi.dwMinorVersion, dvi.dwMajorVersion);
		}
	}
	
	return dwVersion;
}