private void returnBook(string id, TimeSpan ts) { float penalty = 0; string penaltyMsg = ""; if (ts.Days > 0) { penalty = penaltyPerDay * ts.Days; } if (penalty > 0) { penaltyMsg = "You have been imposed a penality of $" + penalty + ". "; } BookControl bc = new BookControl(); bc.returnBook(int.Parse(id), LoginInfo.LoggedInId, penalty); MessageBox.Show(bc.Message + " " + penaltyMsg); loadData(); }