private void OnMovieAdd(object sender, EventArgs e) { var form = new MovieForm(); //modeless :does not block main window //form.Show (); //show the new movie form modally if (form.ShowDialog(this) == DialogResult.OK) { try { _movies.Add(form.Movie); UpdateUI(); } catch (ArgumentException ex) { MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); } catch (ValidationException ex) { MessageBox.Show(ex.Message, "Validation Error", MessageBoxButtons.OK, MessageBoxIcon.Error); } catch (Exception ex) { MessageBox.Show("Save failed", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); //throw; //rethrow existing exception //throw ex; //throwing new exception }; } ; }