private void button1_Click(object sender, EventArgs e) { // Save data or call delegate try { CustomersEntities ce = new CustomersEntities(); ce.Customers.Add(new Customers { Firstname = FirstNameTextBox.Text, Lastname = LastNameTextBox.Text, Address = AddressTextBox.Text, CountryCode = (string)CountryListcomboBox.SelectedValue }); ce.SaveChanges(); //Doesn't actually save. Might need to use an adapter or a 'real' SQL server than .mdf MessageBox.Show("New customer added (or at least want you to think so)"); this.DialogResult = DialogResult.OK; } catch (Exception exp) { //TODO: Validations, and proper error handling MessageBox.Show("An error occoured: " + exp.Message); } }