Question

I am using an edit box as a round counter. I would like when the text = 5 or 10 for it to show this message then it does some functions. but even when the round is 5 or 10, i never get this message ERoundChange is the OnChange event for the ERound(edit box) ; Any idea why its not working? I assume i am using Self wrong?

{Check if round is 5 or 10}
//-----------------------------------------------------
procedure TBaseGameForm.ERoundChange(Sender: TObject);
//-----------------------------------------------------
begin
 if (self.Text = '5') or (self.Text = '10') then
   begin
      showmessage('checking stats for gryph locations on round: '+self.Text);

    end;
end;

Also I change the round at the beginning of each players turn like so

ERound.Text := inttostr(Strtoint(ERound.Text)Mod 10+1);

Answer 1

Since ERoundChange is a method of TBaseGameForm, Self refers to the current instance of TBaseGameForm, that is, to the form, and not the edit box inside it.

Hence, Self.Text is the caption of the form, and not the text inside the edit box. If the edit box is named Edit1, you should do

procedure TBaseGameForm.ERoundChange(Sender: TObject);
begin
  if (Edit1.Text = '5') or (Edit1.Text = '10') then
    ShowMessage('checking stats for gryph locations on round: '+ Edit1.Text);
end;

You could also do

procedure TBaseGameForm.ERoundChange(Sender: TObject);
begin
  if ((Sender as TEdit).Text = '5') or ((Sender as TEdit).Text = '10') then
    ShowMessage('checking stats for gryph locations on round: '+ (Sender as TEdit).Text);
end;

since the control that caused the event is stored in the Sender argument. But since Sender is declared as TObject, you need to cast it to the actual TEdit which it is.

[You could have figured this out yourself. Indeed, the procedure TBaseGameForm.ERoundChange itself has nothing to do with the edit control — sure, it is assigned to an event of this control, but of course you can assign it to other controls as well, and use it in any other way you like. Hence, by itself, it is only associated with TBaseGameForm, so really, Self couldn’t logically refer to anything else.]