How can we put the leading zero in a Number with specifix n Max Digit place holder ??
Is there any Delphi built in function to do this job ??

Example:
» if digit place holder is 5 => 00123
» if digit place holder is 3 => 012

Actually, Delphi has supported to do this kind of job.
Yes, we can use function "Format" strings to do this
But we must do a little trick here to use it appropriately

Here is my example code:
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function GiveLeadingZero(const aNumber, aMaxDigit: Integer): String;
var formatSpecifier: String;
begin
  formatSpecifier := Format('%%.%dd', [aMaxDigit]);

  // formatSpecifier will result like this: '%.5d' if aMaxDigit=5
  Result := Format(formatSpecifier, [aNumber]);
end;

procedure TForm1.Button1Click(Sender: TObject);
var aNumber: Integer;
begin
  if (TryStrToInt(Edit1.Text, aNumber)) then
    Edit2.Text := GiveLeadingZero(aNumber, 5)
  else
    ShowMessage('Value in Edit1 is not a valid integer value');
end;

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To use those code, simply juzt put two TEdit component on the Form with one button to execute the code



I think it solved the problem.