[DayBreak]

Код:

function IsIntWithout(Str:String):Boolean;
var
  i:Integer;
  //LabeledEdit1: TLabeledEdit;
  //Str:String;
begin
  Result:=false;
  //Str:=  Form1.LabeledEdit1.Text;
  if Str='' then exit;

  for i:=1 to Length(Str) do
  if not (Str[i] in ['0'..'9']) then exit;

  Result:=true;
end;

function IsIntWith(Str:String):Boolean;
var
  i:Integer;
begin
  if Length(Str)>0 and (Str[1] in ['+', '-']) then
  Result:=IsIntWithout(Copy(Str,2,Length(Str)-1))
  else
  Result:=IsIntWithout(Str);
end;

В строке номер 21 ругается на Str[1] in ['+', '-']