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To validate the input to a field, it is possible to use the event OnEditFieldCheckInputString

 

In this example we take care that the user cannot enter data into a checkbox field. All other fields are restricted to 30 characters

 

procedure TWPEdTest.DataEditEditFieldCheckInputString(Sender: TObject;

 field: TWPTextObj; var text: string; var abort: Boolean);

var embedded : TWPTextObj;

begin

if field.NameIs('_check') then // we expect a boolean field

begin

  if text=#32 then

  begin

     embedded := field.GetContainedObject([wpobjTextObject]);

    if embedded<>nil then

    begin

      WPSetCheckBoxValue(embedded,not WPGetCheckBoxValue(embedded,true));

      (Sender as TWPRTFEngineEdit).Repaint;

    end;

  end;

   abort := true;

end

else // in any other field limit data entry to 30 characters

 Abort := (text <>#8) and (text<>#127) and not

    (Sender as TWPRTFEngineEdit).Cursor.IsSelected(true) and

     (field.EmbeddedTextLength>30);

end;