#define EXPORT __declspec(dllexport)
EXPORT int CALLBACK MyFunction(char* str);

#include <windows.h>
#include  "mydll.h" 

int WINAPI DllMain(HINSTANCE hInstance, DWORD fdReason, PVOID pvReserved) 
{
  return TRUE;
};

EXPORT int CALLBACK MyFunction(char *str)
{
  Beep( 500 ,  100 );
  MessageBox(NULL, str,  "Function from DLL" , MB_OK);
 	return  1 ;
}

#include <windows.h >

typedef int (WINAPI *PFN_MyFunction) (char *);

int WINAPI WinMain(HINSTANCE hInstance,
                   HINSTANCE hPrevInstance,
                   LPSTR lpCmdLine,
                   int nCmdShow)
{
  HINSTANCE hMyDll;

  if((hMyDll = ::LoadLibrary( "mydll" ))==NULL)
  {
    MessageBox(NULL,  "Cannot load dll!" ,  " " , MB_OK);
    return  1 ;
  }

  PFN_MyFunction pfnMyFunction;

  pfnMyFunction = (PFN_MyFunction)::GetProcAddress(hMyDll,  "MyFunction" );

  try
  {
    int iCode = (*pfnMyFunction)( "Successful execution of dll function!" );
  }
  catch(...)
  {
    MessageBox(NULL,  "Error!" ,  " " , MB_OK);
  }
  ::FreeLibrary(hMyDll);

  return  0 ;
}

LIBRARY mydll

EXPORTS
  MyFunction  @ 1