GetProcAddresses one time - DLL

蓄上篇 DLL。
這一篇VC++ Example: Loading DLLs LoadLibrary and GetProcAddress and FreeLibrary文章就有用這樣的方法：

BOOL GetProcAddresses( HINSTANCE *hLibrary, 
    LPCSTR lpszLibrary, INT nCount, ... )
{
    va_list va;
    va_start( va, nCount );

    if ( ( *hLibrary = LoadLibrary( lpszLibrary ) ) 
        != NULL )
    {
        FARPROC * lpfProcFunction = NULL;
        LPSTR lpszFuncName = NULL;
        INT nIdxCount = 0;
        while ( nIdxCount < nCount )
        {
            lpfProcFunction = va_arg( va, FARPROC* );
            lpszFuncName = va_arg( va, LPSTR );
            if ( ( *lpfProcFunction = 
                GetProcAddress( *hLibrary, 
                    lpszFuncName ) ) == NULL )
            {
                lpfProcFunction = NULL;
                return FALSE;
            }
            nIdxCount++;
        }
    }
    else
    {
        va_end( va );
        return FALSE;
    }
    va_end( va );
    return TRUE;
}

使用方法就是：

#include <windows.h>

typedef int ( WINAPI *MESSAGEBOX ) 
    ( HWND , LPCSTR, LPCSTR, DWORD );
typedef int ( WINAPI *MESSAGEBOXEX ) 
    ( HWND , LPCSTR, LPCSTR, DWORD , WORD );

void main(void)
{
    MESSAGEBOX lpfMsgBox = NULL;
    MESSAGEBOXEX lpfMsgBoxEx = NULL;
    HINSTANCE hLib;
    if(GetProcAddresses( &hLib, "User32.dll", 2,
        &lpfMsgBox, "MessageBoxA",
        &lpfMsgBoxEx, "MessageBoxExA" ) )
    {
        lpfMsgBox( 0, "Test1", "Test1", MB_OK );
        lpfMsgBoxEx( 0, "Test2", "Test2", MB_OK, 
            MAKELANGID( LANG_ENGLISH, SUBLANG_ENGLISH_US ) );
    }
    if ( hLib != NULL )
        FreeLibrary( hLib );
}

但是他還是用了typedef，其實直接宣告function pointer就可以了。