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();
}