/// Вызов окна диалога для выбора открываемого файла
QString getOpenFileName(QWidget* parent, const char* caption, const char* directory, const char* filter)
{
    const int NAME_SIZE = 550;
    char fname[NAME_SIZE] = {0};        ///< буфер для имени файла
    bool result = false;

#ifdef Q_WS_WIN
    OPENFILENAME ofn;                    ///< структура диалога открытия файла
    ::ZeroMemory(&ofn, sizeof(ofn));
    ofn.lStructSize = 88;
    ofn.hwndOwner = (parent) ? parent -> winId() : 0;
    ofn.lpstrFile = fname;
    ofn.nMaxFile = sizeof(fname);
    ofn.lpstrFilter = filter;
    ofn.nFilterIndex = 0;
    ofn.lpstrFileTitle = 0;
    ofn.nMaxFileTitle = 0;
    ofn.lpstrInitialDir = directory;
    ofn.lpstrTitle = caption;
    ofn.Flags = OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST;
 
    if(::GetOpenFileName(&ofn) == 1) result = true;
#endif // Q_WS_WIN

    return (result) ? QString(fname) : QString("");
}

/// Вызов окна диалога для выбора открываемых файлов
QStringList getOpenFileNames(QWidget* parent, const char* caption, const char* directory, const char* filter)
{
    const int NAME_SIZE = 5500;
    char fname[NAME_SIZE] = {0};        ///< буфер для имени файла
    QStringList list;

#ifdef Q_WS_WIN
    OPENFILENAME ofn;                    ///< структура диалога открытия файла
    ::ZeroMemory(&ofn, sizeof(ofn));
    ofn.lStructSize = 88;
    ofn.hwndOwner = (parent) ? parent -> winId() : 0;
    ofn.lpstrFile = fname;
    ofn.nMaxFile = sizeof(fname);
    ofn.lpstrFilter = filter;
    ofn.nFilterIndex = 0;
    ofn.lpstrFileTitle = 0;
    ofn.nMaxFileTitle = 0;
    ofn.lpstrInitialDir = directory;
    ofn.lpstrTitle = caption;
    ofn.Flags = OFN_ALLOWMULTISELECT | OFN_EXPLORER | OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST;

    if(::GetOpenFileName(&ofn) == 1)
    {
        if(ofn.nFileExtension)
            list << QString(fname);
        else if(ofn.nFileOffset)
        {
            QString path(QString(fname) + QDir::separator()), name("");
            for(int i=ofn.nFileOffset, j=ofn.nFileOffset+1; fname[i]!=0 || fname[j]!=0 || j<sizeof(fname); ++i,
                ++j)
            {
                if(fname[i] != 0)
                    name += QChar(fname[i]);
                if(fname[j] == 0)
                    list << QString(path + name),
                    name.clear(),
                    ++i, ++j;
                if(fname[i] == 0 && fname[j] == 0)
                    break;
            }
        }
    }
#endif // Q_WS_WIN

    return list;
}

QFileDialog::QFileDialog(QWidget *parent,
                     const QString &caption,
                     const QString &directory,
                     const QString &filter)
    : QDialog(*new QFileDialogPrivate, parent, 0)
{
    Q_D(QFileDialog);
    d->init(directory, filter, caption);
}

int QDialog::exec()
{
// ...

(void) eventLoop.exec();

/// ............
}