private void btnUpdateTrainee_Click(object sender, RoutedEventArgs e) { var trainee = bl.getTraineeList().Find(x => x.ID == 317801157);//the id can be given in a textbox in the future bl.updateTrainee(trainee); try { bl.updateTrainee(Abigail); } catch (Exception ex) { MessageBox.Show(ex.Message); } }