使用SendMessage函数，控制EDIT控件的KEYUP事件

procedure TfmPcSpriceAdj.btnGdsTypeKeyUp(Sender: TObject; var Key: Word;
  Shift: TShiftState);
var
  str1,str2: string;
begin
  inherited;
  case Key of
    VK_RETURN:
      begin
        Self.Enabled := False;
        ShowGridBySql(btnGdsType,'GdsType',btnGdsType.Text,str1,str2);
        btnGdsType.Text := str1;
        btnGdsType.Hint := str2;
        if str1 <> '' then SendMessage(Handle, WM_NEXTDLGCTL, 0, 0);
        Self.Enabled := True;
      end;
    VK_ESCAPE: btnGdsType.Text := '';
  end;
end;

procedure TfmPcSpriceAdj.btnGdsTypePropertiesButtonClick(Sender: TObject;
  AButtonIndex: Integer);
begin
  inherited;
  btnGdsType.Text := '';
  SendMessage(btnGdsType.Handle,WM_KEYUP,VK_RETURN,0);
end;