function CheckInteger(value: String): Boolean;
var
  I, Code : Integer;
begin
  Val(value, I, Code);
  if Code<>0 then
    Result := False
  else
    Result := True;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
 if CheckInteger(Edit1.Text) = True then
    ShowMessage('Hasil: Integer')
 else
    ShowMessage('Hasil: Bukan Integer');
end;

    try
       x := StrToInt(Edit1.Text);
      showmessage('Hasil Integer');
    except
      x := 0;
      showmessage('Hasil Bukan Integer');
    end;