private void btnMakeBill_Click(object sender, EventArgs e) { string b_id = txtBillID.Text; string s_id = CurrentAccount; string cus_name = txtNameC.Text; string cus_phone = txtPhoneC.Text; string email = txtEmailC.Text; string add = rtbAddC.Text; string cmt = rtbCmt.Text; DataProcess dt = new DataProcess(); if (dt.AddBill(b_id, s_id, cus_name, cus_phone, email, add, TotalAmount, cmt, cart)) { MessageBox.Show("Order Success"); } else { MessageBox.Show("Error"); } }