Why define NewCols in Grids.pas

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kinlion:
When using TStringGrid, I hide some columns in the Object Inspector. Then I want to get the count of visible columns by calling StringGrid.Columns.VisibleColCount, but the result is wrong because it counts the invivible columns.
Deep into the grids.pas, I found there is a defeine at the head of the file:

--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---{$define NewCols}and the function:

--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---function TGridColumns.GetVisibleCount: Integer;{$ifNdef newcols}var i: Integer;{$endif}begin {$ifdef newcols} result := Count; {$else} result := 0; for i:=0 to Count-1 do if Items[i].Visible then inc(result); {$endif}end;
The definition makes the function igoring Coulmn's Visible property.
Why?

kinlion:
OK. I understand it now after reading this function:

--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---function TGridColumn.GetWidth: Integer;var tmpGrid: TCustomGrid;begin {$ifdef newcols} if not Visible then exit(0); {$endif} if FWidth=nil then result := GetDefaultWidth else result := FWidth^; if (result<0) then begin tmpGrid := Grid; if tmpGrid<>nil then result := tmpGrid.DefaultColWidth; end;end;
To define NewCols means to treat the unvisible columns as a zero-widthed column instead of removing it from columns logically. Maybe for speeding up code.

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