problems with the use of writeln

[frederic]

in an other thread on this forum i was invited to use writeln  calls to look for abnormal values in the code.

 writeln is not used by me up till now ; i am used to memo for these cases;

the problem is when i use the writeln in loops and i look back at the result ,a lot of times(unfornutaly not always) the text stops in de middle of a line  .(with a file of appr 4000 lines 3 lines before the end);

i use following:

Code: [Select]

var
  Form1: TForm1;
   testtextfile, followtesttextfile: Text; }
    ''''''
    ''''

  procedure TForm1.FormCreate(Sender: TObject);
  begin
  Assignfile(testtextfile,'feedunittest');
  ReWrite(testtextfile);
   end;

  procedure Tform1.XXXXX ;
var mmm:integer;
     begin
     for mmm:=0 to 4000 do
     begin
    // FDTXAxarr1   FXaxdayspassed1 are dynamic arrays
     WriteLn(testtextfile, 'FDTXAxarr1['+inttostr(mmm)+']= '+ datetimetostr(FDTXAxarr1[mmm])+ ';'+floattostr(FXaxdayspassed1[mmm]));
     end;

    procedure TForm1.FormClose(Sender: TObject; var CloseAction: TCloseAction);
   begin
   CloseFile(testtextfile);
    end;

               
did i forget something??

frederic

[rvk]

You could try Flush(testtextfile); before closing the file but that shouldn't be necessary.

[derek.john.evans]

Maybe TForm1.FormClose() has become disconnected from the TForm. ie: You might have deleted FormClose from the object inspector.

Either way, you should open/close the file in the same function. That way you ensure the file is completely written out.

[kpeters58]

Not sure if this could be a form of range check issue? You could turn Range Checking on and see.

Either way, I always do something along the lines of the code below for such purposes:

Code: [Select]

procedure Tform1.XXXXX;
var
  sl: TStringList;
  mm: Integer;

begin
  sl := TStringList.Create;
  try
    for mmm := 0 to 4000 do
      sl.Add('FDTXAxarr1[' + IntToStr(mmm) + '] = ' + FormatDateTime('yyyy-mm-dd', FDTXAxarr1[mmm]) + ';' + FloatToStr(FXaxdayspassed1[mmm]));
    //
    sl.SaveToFile('feedunittest');
  finally
    if Assigned(sl) then
      sl.Free;
end;

[frederic]

Thanks for your reactions,

1. rvk    flush(testtextfile) before closefile(testtextfile ) in the formclose did't improve the situation.

Wat i didn't mention before is, that just before writeln is used in the loop ,a memo is filled with the same string and that is complete and oke.
I did 3 test with the flush : 

FDTXAxarr1[2543]= 21-11-2014 17:28:00;4,99607843137255
FDTXAxarr1[254 

FDTXAxarr1[3053]= 24-11-2014 17:29:00;5,99803921568627
LAST on DAy FDTXAxarr1[3054]= 24-   

FDTXAxarr1[8651]= 9-12-2014 17:28:00;16,9960784313725
FDTXAxarr1[8652]= 9-12-2014 17:29:00;16,9980392156863
LAST on     

2. derek
indeed by assigning and closing the file in the xxxx- procedure the whole file is listed by writeln

3 . kpeters   :the range of the dynamic arrays was set very ample

so the issue is solved although it makes me think why

thanks again

frederic