private void comboBox2_SelectedIndexChanged(object sender, EventArgs e) { if (comboBox2.SelectedIndex < 0) { return; } ATINChamCongEntities context = new ATINChamCongEntities(); var calamviec = context.spGetCaLamViec((comboBox2.SelectedItem as CaLamViec).MaCaLamViec).FirstOrDefault(); textBox10.Text = calamviec.TongGio.ToString(); textBox11.Text = calamviec.DiemCong.ToString(); }