protected void Page_Load(object sender, EventArgs e) { Response.AppendHeader("Access-Control-Allow-Origin", "*"); string vouchercode = Request["vouchercode"]; string userid = Request["userid"]; // kiem tra voucher code phai di kem voi userid do, vi moi voucher thuoc ve 1 user duy nhat. VoucherManager vm = new VoucherManager(); VouchersTBx v = vm.CheckVoucherCode(vouchercode, userid); if (v != null) { Response.Write(v.VoucherDefaultCost); // voucher chua xai! } else { Response.Write("1"); // voucher vi pham error } }