private void CreateButton_Click(object sender, EventArgs e) { var id = Phonebook.Contacts.OrderByDescending(c => c.Id).First().Id; var contact = new Contact(++id, nameTextbox.Text, emailTextbox.Text, dobPicker.Value.Date, numberTextbox.Text); Phonebook.AddContactToList(contact); var reader = new JsonDataAccess(); reader.SaveData(); MessageBox.Show("Contact created."); Close(); }