Итерация подкаталогов

procedure TFormList.RecurseDir(PathInicial: string);
var
  SearchRec: TSearchRec;
  Result: integer;
  tmpName: string;
begin
  DirectoryListBox1.Directory := PathInicial;
  Result := FindFirst(PathInicial + '\*.*', faAnyFile, SearchRec);
  while Result = 0 do
  begin
    if ExtOk(SearchRec.Name) then
      { если каталог... }
      if SearchRec.Attr and faDirectory > 0 then
        { рекурсивно обрабатываем... }
        RecurseDir(PathInicial + '\' + SearchRec.Name)
      else
      begin
        tmpName := PathInicial + '\' + SearchRec.Name;
        tmpName := Copy(tmpName,
          Pos(PathOrigen, tmpName) + Length(PathOrigen),
          Length(tmpName) - Length(PathOrigen));
        ListBox1.Items.Add(LowerCase(tmpName));
      end;
    Application.ProcessMessages;
    Result := FindNext(SearchRec);
  end;
  DirectoryListBox1.Directory := PathInicial;
end;