C / C++ / MFC

journalHook = SetWindowsHookEx(WH_JOURNALPLAYBACK, (HOOKPROC)WDChangeProc, hInst, 0);

typedef HRESULT (*PROCHICON)(HICON*); 
typedef CString (*PROCCSTRNAME)(); 
typedef CString (*PROCCSTRCONT)(CString); 

LoadButtonPluginDLL(CString DLLPath,CString &ButtonText,HICON &ImageHandle,CString &ButtonContent)
{
PROCHICON ProcButtonHicon;
PROCCSTRNAME ProcButtonName;
PROCCSTRCONT ProcButtonContent;
HINSTANCE hLib = ::LoadLibrary(DLLPath); //load the plugin libarary dll//    
if(hLib==NULL)
{
 MessageBox(_T("Fails To Load Dll"));
return;
}

ProcButtonHicon =(PROCHICON)::GetProcAddress(hLib,"GetButtonImage"); 
if(ProcButtonHicon == NULL) //if dll is not loaded
{
  ::FreeLibrary(hLib);
  CoUninitialize();
 return;
} 
ProcButtonName =(PROCCSTRNAME)::GetProcAddress(hLib,"GetButtonText");  
if(ProcButtonName == NULL) 
{
 ::FreeLibrary(hLib);
 CoUninitialize();
 return;
}  
ProcButtonContent= (PROCCSTRCONT)::GetProcAddress(hLib,"GetPluginContent");
if(ProcButtonContent == NULL) //if dll is not loaded
{
::FreeLibrary(hLib);
CoUninitialize();
return;
}            
 ((PROCHICON)ProcButtonHicon)(&ImageHandle);
ButtonText =((PROCCSTRNAME)ProcButtonName)();  
ButtonContent =((PROCCSTRCONT)ProcButtonContent)("1");  

if(hLib)
 FreeLibrary(hLib); //free the libaray    
}