c# - 使用 C# 的 Paypal PDT

Question

我正在尝试使用带有 C# 的 pdt 来实现购物车跟踪系统。 我遇到的麻烦是找到一个 paypal 成功回发的例子，尤其是在有多个项目的情况下! 我们将不胜感激(有些代码会更好 :D)! 谢谢

Answer 1

下面的代码解析 PDT 响应:

using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Configuration;
using System.Globalization;
using System.Net;
using System.IO;
using System.Text;

namespace PayPal
{
    public static class PaymentDataTransfer 
    {
        private const string AppSetting_Identity = "PayPal.PaymentDataTransfer.Identity";
        private const string AppSetting_ServiceUrl = "PayPal.PaymentDataTransfer.ServiceUrl";

        public class TransactionStatus
        {
            public bool Success { get; set; }
            public int ErrorCode { get; set; }
            public NameValueCollection Parameters { get; set; }

            public float PaymentGross { get; set; }
            public string Currency { get; set; }

            public string Invoice { get; set; }
            public PayerInformation Payer { get; set; }
            public CartItem[] CartItems;
        }

        public class PayerInformation
        {
            public string FirstName { get; set; }
            public string LastName { get; set; }
            public string Email { get; set; }
        }

        public class CartItem
        {
            public int Number { get; set; }
            public string Name { get; set; }
            public int Qunatity { get; set; }
            public float GrossPrice { get; set; }
        }

        public static TransactionStatus GetTransactionStatus(string transactionToken)
        {
            return GetTransactionStatus(transactionToken, false);
        }

        public static TransactionStatus GetTransactionStatus(string transactionToken, bool sandbox)
        {

#if ParsingTest
            string response =
                @"SUCCESS
mc_gross=1100.00
invoice=334354
protection_eligibility=Eligible
address_status=confirmed
item_number1=1
tax=0.00
item_number2=2
payer_id=DSFSDFSDFSDF
address_street=1+Main+St
payment_date=04%3A13%3A49+Oct+20%2C+2011+PDT
payment_status=Completed
charset=windows-1252
address_zip=95131
mc_shipping=0.00
mc_handling=0.00
first_name=Test
mc_fee=32.20
address_country_code=US
address_name=Test+User
custom=
payer_status=verified
business=yourbusiness%40business.com
address_country=United+States
num_cart_items=2
mc_handling1=0.00
mc_handling2=0.00
address_city=San+Jose
payer_email=payer_email%40business.com
mc_shipping1=0.00
mc_shipping2=0.00
txn_id=0SDFSDFSDFSDFD
payment_type=instant
last_name=User
address_state=CA
item_name1=First+test+item
receiver_email=yourbusiness%40business.com
item_name2=Second+test+item
payment_fee=32.20
quantity1=1
quantity2=1
receiver_id=SDFGDFGDFGDFDFG
txn_type=cart
mc_gross_1=1000.00
mc_currency=USD
mc_gross_2=100.00
residence_country=US
transaction_subject=Shopping+Cart
payment_gross=1100.00";

#else
            string authToken = GetAppSetting(AppSetting_Identity, sandbox);
            string serviceUrl = GetAppSetting(AppSetting_ServiceUrl, sandbox);
            string query = string.Format("cmd=_notify-synch&tx={0}&at={1}", transactionToken, authToken);

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(serviceUrl);

            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";
            request.ContentLength = query.Length;

            using (var requestStreamWriter = new StreamWriter(request.GetRequestStream(), Encoding.ASCII))
            {
                requestStreamWriter.Write(query);
                requestStreamWriter.Close();
            }

            string response;

            // Do the request to PayPal and get the response
            using(StreamReader stIn = new StreamReader(request.GetResponse().GetResponseStream()))
            {
                response = stIn.ReadToEnd();
                stIn.Close();
            }
#endif

            string[] lines = response.Split(new []{"\n", "\r\n"}, StringSplitOptions.None); // splitting up by line breaks

            var result = new TransactionStatus
                             {
                                 Success = lines[0] == "SUCCESS",
                                 Parameters = new NameValueCollection()
                             };

            for(int i=1; i < lines.Length; i++)
            {
                string line = lines[i];

                string[] keyValuePair = lines[i].Split(new [] {'='});

                if(keyValuePair.Length == 2)
                {
                    result.Parameters.Add(UrlDecode(keyValuePair[0]), UrlDecode(keyValuePair[1]));
                } 
                else
                {
                    const string errorCodePrefix = "Error:";

                    if(line.StartsWith(errorCodePrefix))
                    {
                        result.ErrorCode = Int32.Parse(line.Substring(errorCodePrefix.Length));
                    }
                }
            }

            if(result.Success)
            {
                result.Invoice = result.Parameters["invoice"];

                result.Payer = new PayerInformation
                                   {
                                       FirstName = result.Parameters["first_name"],
                                       LastName = result.Parameters["last_name"],
                                       Email = result.Parameters["payer_email"]
                                   };

                float paymentGross;
                result.PaymentGross = float.TryParse(result.Parameters["mc_gross"], 
                                      NumberStyles.Float, 
                                      CultureInfo.InvariantCulture, 
                                      out paymentGross) ? paymentGross : 0.0f;

                result.Currency = result.Parameters["mc_currency"];

                int cartItemsNumber;
                if (int.TryParse(result.Parameters["num_cart_items"], out cartItemsNumber) && cartItemsNumber > 0)
                {
                    var cartItems = new List<CartItem>();

                    for(int i=1; i <= cartItemsNumber; i++)
                    {
                        cartItems.Add(new CartItem
                                          {
                                              Number = int.Parse(result.Parameters["item_number" + i], CultureInfo.InvariantCulture),
                                              Name =  result.Parameters["item_name" + i],
                                              Qunatity = int.Parse(result.Parameters["quantity" + i], CultureInfo.InvariantCulture),
                                              GrossPrice = float.Parse(result.Parameters["mc_gross_" + i], CultureInfo.InvariantCulture)
                                          });
                    }

                    result.CartItems = cartItems.ToArray();
                }
            }

            return result;
        }

        private static string UrlDecode(string encodedText)
        {
            return Uri.UnescapeDataString(encodedText.Replace("+", " "));
        }

        private static string GetAppSetting(string settingName, bool sandbox)
        {
            return ConfigurationManager.AppSettings[settingName + (sandbox ? "_sandbox" : string.Empty)];
        }
    }
}

来自 web.config 的配置部分:

<appSettings>
    .....

    <!-- PayPal -->
    <add key="PayPal.PaymentDataTransfer.Identity" value="....." />
    <add key="PayPal.PaymentDataTransfer.Identity_sandbox" value="....." />
    <add key="PayPal.PaymentDataTransfer.ServiceUrl" value="https://www.paypal.com/cgi-bin/webscr" />
    <add key="PayPal.PaymentDataTransfer.ServiceUrl_sandbox" value="https://www.sandbox.paypal.com/cgi-bin/webscr" />
</appSettings>