Get directory size from delphi

// Get directory size

function GetDirSize(dir: string; subdir: Boolean): Longint;
var
  rec: TSearchRec;
  found: Integer;
begin
  Result := 0;
  if dir[Length(dir)] <> '\' then dir := dir + '\';
  found := FindFirst(dir + '*.*', faAnyFile, rec);
  while found = 0 do
  begin
    Inc(Result, rec.Size);
    if (rec.Attr and faDirectory > 0) and (rec.Name[1] <> '.') and (subdir = True) then
      Inc(Result, GetDirSize(dir + rec.Name, True));
    found := FindNext(rec);
  end;
  FindClose(rec);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  label1.Caption := FloatToStr(GetDirSize('e:\download', False) / Sqr(1024)) + ' MBytes';
  label2.Caption := FloatToStr(GetDirSize('e:\download', True) / Sqr(1024)) + ' MBytes';
end;