Delphi does not write to txt file

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4

The code below creates the txt file but does not write to it. Which may be?

procedure TForm1.Button4Click(Sender: TObject);
var
arq: TextFile;
begin
qr.Active:= true;
qr.First;
  try
    AssignFile(arq, 'd:\\tabuada.txt');
    Rewrite(arq);
    writeln(arq, 'teste');
    while not qr.Eof do
      begin
      writeln(arq, qr.FieldValues['ine'] + ';' + qr.FieldValues['cmp'] + ';' + qr.FieldValues['cbo'] + ';' + qr.FieldValues['pa'] + ';' + qr.FieldValues['idade'] + ';' + '1;' + qr.FieldValues['quant'] + ';' + qr.FieldValues['profissional'] + ';' + qr.FieldValues['cnesdescricao'] + ';' + qr.FieldValues['cbodescricao'] + ';' + qr.FieldValues['padescricao']);
      qr.Next;
      end;

    CloseFile(arq);
    ShowMessage('ok2');
  except
  end;
end;

Shows no error and does not show ok2'

delphi
  • 1

    The fact of not showing error is due to you having a Try..Except without proper treatment. Put a ShowMessage no Except with the on E.Exception do with the error message.

2 answers

3

Before changing the file check whether or not it exists right after the AssignFile(), doing as follows:

if FileExists('d:\\tabuada.txt') then
   Append(arq)
else
   Rewrite(arq);

In place qr.FieldValues replace with qr.FieldByName(), respecting the type of the bank fields.

Varchar: qr.FieldByName('NOME_CAMPO').AsString;
Integer: qr.FieldByName('NOME_CAMPO').AsInteger;
Numeric: qr.FieldByName('NOME_CAMPO').AsFloat;
  • 3

    +1 he has no problem with his code, the only "problem" there is permission of I/What is being masked in try

1


Avoid creating empty Try-excepts. Problem information will probably appear if you change the except for:

except
  on E: Exception do
    ShowMessage(E.Message);
end;

As for the problem, you may not be allowed to create a file in this directory D:, which would be solved by running the executable as an administrator, or saving in a folder other than the root. But this can only be said with certainty through code on except.

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