If and then statement not working 4

[Mezzzo]

procedure TDoorMain.RadioButtonInsetClick(Sender: TObject);
begin
If RadioButtonInset.Checked = True and CboNumberOfDoors.items.indexof('1') then
begin
PanelSinInset.Visible := True;
end;
end.

The code is to allow the panel to visible if
a number in the combo is 1.
Please help. I get an error that the opertaor not applicable.

 

[Jonah86]

I don't think you need that begin in the if statement. I could be wrong. Since the end. is only needed once on the form, I think, it doesn't really relate to the first begin there. So you, in essence, have 2 begins and only one end;. I would try that, though there's a strong chance that I'm wrong...I'm pretty new at this.

 

[Zathras]

Delphi doesn't always interpret complex statements the way you think it should. Use parentheses to make your intent clear:
[blue]

If  (RadioButtonInset.Checked = True) and (CboNumberOfDoors.items.indexof('1')>=0) then

[/color]
In this particular case, the "operator not applicable" is because the expression

    CboNumberOfDoors.items.indexof('1')

is not a boolean. (It is an integer.) Consequently, you cannot use it directly with if

 

[hilfy]

Also, you don't have to use "= True" or "= False" when evaluating things that are supposed to give a boolean value. You could rewrite your If statement as:
[blue]
If RadioButtonInset.Checked and (CboNumberOfDoors.items.indexof('1')>=0) then
[/blue]

If you were looking for a false value, you'd do:
[blue]
If Not RadioButtonInset.Checked ...
[/blue]

-D

 

[LucieLastic]

You could simplify this in to one statement:-

PanelSinInset.Visible := RadioButtonInset.Checked and (CboNumberOfDoors.items.indexof('1')>=0);

lou

 

[LucieLastic]

Actually, shouldn't it be :-

PanelSinInset.Visible := RadioButtonInset.Checked and (CboNumberOfDoors.items[CboNumberOfDoors.itemIndex]='1');

 

[towerbase]

Lou

Your code simplification is incorrect. It doesn't have the same effect as Mezzzo's original code.

Take for example the situation when PanelSinInset.Visible is already TRUE.

Now if RadioButtonInset.Checked is FALSE your code would set PanelsSinInset.Visible to FALSE but in Mezzzo's original code he would leave PanelSinInset.Visible as TRUE.





Andrew
Hampshire, UK

 

[LucieLastic]

hi Andrew

You are right. I was just going off the textual bit "The code is to allow the panel to visible if a number in the combo is 1." so I assumed if it wasn't '1' then it wouldn't be visible.

lou

 

[towerbase]

Lou,

Your interpetation of the "specification" may be correct but, on the other hand, there may be something else on the form such as a checkbox which, if checked, also requires the panel to be visible.

Without knowing this, it seems unwise to me, to change the meaning of Mezzzo's code without some kind of warning.



Andrew
Hampshire, UK