public ActionResult ValiderPanier(PanierViewModel model) { ServicePointManager.Expect100Continue = true; ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12; if (!ModelState.IsValid) { return(View("Panier", model)); } Session["Panier"] = model; string serverURL = HttpContext.Request.Url.GetLeftPart(UriPartial.Authority) + VirtualPathUtility.ToAbsolute("~/"); SetExpressCheckoutResponse transactionResponse = paypalService.SendPayPalSetExpressCheckoutRequest(model, serverURL); if (transactionResponse == null || transactionResponse.ResponseStatus != Core.Transcoder.PayPalMvc.Enums.ResponseType.Success) { string errorMessage = (transactionResponse == null) ? "Null Paypal Transaction Response" : transactionResponse.ErrorToString; Debug.WriteLine("Error initiating PayPal SetExpressCheckout transaction. Error: " + errorMessage); return(RedirectToAction("Panier", model)); } FlashMessage.Confirmation(UiStrings.add_conversion_message_cart_validated); return(Redirect(string.Format(Configuration.Current.PayPalRedirectUrl, transactionResponse.TOKEN))); }