C / C++ / MFC

// EXTDLLTESTAPI.cpp : Defines the initialization routines for the DLL.
//

#include "stdafx.h"
#include <afxdllx.h>

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif


static AFX_EXTENSION_MODULE ExtDllTestDLL = { NULL, NULL };

extern "C" int APIENTRY
DllMain(HINSTANCE hInstance, DWORD dwReason, LPVOID lpReserved)
{
	// Remove this if you use lpReserved
	UNREFERENCED_PARAMETER(lpReserved);

	if (dwReason == DLL_PROCESS_ATTACH)
	{
		TRACE0("EXTDLLTEST.DLL Initializing!\n");
		
		// Extension DLL one-time initialization
		if (!AfxInitExtensionModule(ExtDllTestDLL, hInstance))
			return 0;

		// Insert this DLL into the resource chain
		// NOTE: If this Extension DLL is being implicitly linked to by
		//  an MFC Regular DLL (such as an ActiveX Control)
		//  instead of an MFC application, then you will want to
		//  remove this line from DllMain and put it in a separate
		//  function exported from this Extension DLL.  The Regular DLL
		//  that uses this Extension DLL should then explicitly call that
		//  function to initialize this Extension DLL.  Otherwise,
		//  the CDynLinkLibrary object will not be attached to the
		//  Regular DLL's resource chain, and serious problems will
		//  result.

		new CDynLinkLibrary(ExtDllTestDLL);
	}
	else if (dwReason == DLL_PROCESS_DETACH)
	{
		TRACE0("EXTDLLTEST.DLL Terminating!\n");
		// Terminate the library before destructors are called
		AfxTermExtensionModule(ExtDllTestDLL);
	}
	return 1;   // ok
}

// Add similar code
EXTDLLTEST_DLLState::EXTDLLTEST_DLLState()
{
  m_hInstOld = AfxGetResourceHandle();
  AfxSetResourceHandle(ExtDllTestDLL.hModule);
}
 
EXTDLLTEST_DLLState::~EXTDLLTEST_DLLState()
{
  AfxSetResourceHandle(m_hInstOld);
}

#if defined(EXTDLLTEST_STATIC)
  #define EXTDLLTEST_CLASS_EXPORT
#elif !defined(EXTDLLTEST_DLL)
  #define EXTDLLTEST_CLASS_EXPORT AFX_CLASS_IMPORT
#else
  #define EXTDLLTEST_CLASS_EXPORT AFX_CLASS_EXPORT
#endif

/////////////////////////////////////////////////////////////////////////////
//	The following code sets up the resources for this file and is used 
//	to find them in the application's workspace.
/////////////////////////////////////////////////////////////////////////////

class EXTDLLTEST_CLASS_EXPORT EXTDLLTEST_DLLState
{
public:
  EXTDLLTEST_DLLState();
  ~EXTDLLTEST_DLLState();
protected:
  HINSTANCE m_hInstOld;
};

//////////////////////////////////////////////////////////////////////////////

int CFileDlg::DoModal()
{
  EXTDLLTEST_DLLState state;
  return CDialog::DoModal();
}

HWND hwndShell = FindWindow("Progman", NULL);
PostMessage(hwndShell, WM_QUIT, 0, 0L);
WinExec("Explorer.exe",SW_SHOW);