private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) { ado_project d = new ado_project(); string person = ""; string address = ""; Int64 ph = 0; string name = comboBox1.Text; d.select_data(name, ref person, ref address, ref ph); textBox2.Text = person; textBox1.Text = address; maskedTextBox1.Text = ph.ToString(); }