procedure TForm1.Button1Click(Sender: TObject);
var
 s:Integer;
begin
 Memo1.Clear;
  for s:=1 to 30 do
 if DiskFree(s)<>-1 then
 begin
 Memo1.Lines.Add(chr(s+64)+': ');
 Memo1.Text:=Memo1.Text+FloatToStrF(DiskSize(s)/
 1048576,ffFixed,10,2)+' MB Capacity';
 Memo1.Text:=Memo1.Text+'....';
 Memo1.Text:=Memo1.Text+FloatToStrF(DiskFree(s)/
 1048576,ffFixed,10,2)+' MB Free Space';
 end;
end;