private void button4_Click(object sender, EventArgs e) // save button { String n = textBox2.Text; String a = textBox3.Text; String p = textBox4.Text; String em = textBox5.Text; String w = textBox6.Text; if (String.IsNullOrEmpty(n) || String.IsNullOrEmpty(p)) { MessageBox.Show("empty name or phone"); return; } currCustomer.Update(n, a, p, em, w); LoadAll(); }