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procedure TForm1.FormKeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
if key=vk_return then
begin
   key:=0;
   keybd_event(vk_tab,0,0,0);
   keybd_event(vk_tab,0, KEYEVENTF_KEYUP,0);
end;
end;					

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procedure TForm1.FormKeyPress(Sender: TObject; var Key: Char);
begin
 if Key = #13 then begin
  Key := #0;
  PostMessage(Handle, WM_NextDlgCtl, 0, 0);
 end;
end;