PayPal IPN 集成（快速结帐 - Razor/C#）

Question

我目前正在尝试将 PayPal 与我的网站集成，并且一切顺利 - 直到我们进行 IPN 检查。

它一直到 if/elseif/else 块，这就是它结束的地方。它输出一条消息，内容如下：

“无效状态。form_charset=UTF8”

这是我的代码。

@using System.Collections.Generic
@using System.Text
@using System.Web
@using System.Web.UI
@using System.Web.UI.HtmlControls
@using System.Web.UI.WebControls
@using System.ComponentModel

@{
    Layout = "~/_SiteLayout.cshtml";
    Page.Title = "Checkout | SSSSS";

    string postUrl = "https://www.paypal.com/cgi-bin/webscr";
    HttpWebRequest req = (HttpWebRequest)WebRequest.Create(postUrl);

    //Set values for the request back
    req.Method = "POST";
    req.ContentType = "application/x-www-form-urlencoded";
    byte[] param = Request.BinaryRead(HttpContext.Current.Request.ContentLength);
    string strRequest = System.Text.Encoding.UTF8.GetString(param);
    string ipnPost = strRequest;
    strRequest += "&cmd=_notify-validate";
    req.ContentLength = strRequest.Length;

    //for proxy
    //WebProxy proxy = new WebProxy(new Uri("http://url:port#"));
    //req.Proxy = proxy;

    //Send the request to PayPal and get the response
    StreamWriter streamOut = new StreamWriter(req.GetRequestStream(), 
                             System.Text.Encoding.UTF8);
    streamOut.Write(strRequest);

    streamOut.Close();

    StreamReader streamIn = new StreamReader(req.GetResponse().GetResponseStream());
    string strResponse = streamIn.ReadToEnd();
    streamIn.Close();

    /*/ logging ipn messages... be sure that you give write
    // permission to process executing this code
    string logPathDir = ResolveUrl("Messages");
    string logPath = string.Format("{0}\\{1}.txt", 
                     Server.MapPath(logPathDir), DateTime.Now.Ticks);
    File.WriteAllText(logPath, ipnPost);
    /*/

}
@if (strResponse == "VERIFIED")
{
    /*---------------- WILL DO OTHER CHECKS LATER    ------------------*/
    //check the payment_status is Completed
    <p>status is verified</p>
    //check that txn_id has not been previously processed
    //check that receiver_email is your Primary PayPal email
    //check that payment_amount/payment_currency are correct
    //process payment
}
else if (strResponse == "INVALID")
{
    //log for manual investigation
    <p>status is invalid.</p>

<p>@ipnPost</p>
}
else
{
    //log response/ipn data for manual investigation
    <p>status is invalid.</p>
<p>@ipnPost</p>
}

我完全不知道为什么这不能按预期工作；如果有任何帮助，我将不胜感激。

Answer 1

我对 Razor 不是很流利，但这是我的 asp.net 网络表单之一。我相信这是来自另一个网站（或者大部分都是），遗憾的是我不记得在哪里。所以这段代码的基础知识不是我的功劳。

string strLive = "https://www.paypal.com/cgi-bin/webscr";
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(strLive); 
req.Method = "POST";
req.ContentType = "application/x-www-form-urlencoded";
byte[] param = Request.BinaryRead(HttpContext.Current.Request.ContentLength);
string strRequest = Encoding.ASCII.GetString(param);
strRequest += "&cmd=_notify-validate";
req.ContentLength = strRequest.Length;

StreamWriter streamOut = new StreamWriter(req.GetRequestStream(), System.Text.Encoding.ASCII);
streamOut.Write(strRequest);
streamOut.Close();
StreamReader streamIn = new StreamReader(req.GetResponse().GetResponseStream());
string strResponse = streamIn.ReadToEnd();
streamIn.Close();

NameValueCollection ppDetails = HttpUtility.ParseQueryString(strRequest);
if (strResponse == "VERIFIED"){
if (ppDetails["payment_status"] == "Completed"){
//yay, give them goodies
} else if (strResponse == "INVALID"){
//log IP and possibly block them from your web services if malicious
} else {
//log response/ipn data for manual investigation
}
}

主要区别似乎是您使用 UTF8，而我拥有的代码使用 ASCII。我还添加了“ppDetails”部分，让您了解如何处理变量。

希望对您有所帮助。我花了很长时间才弄明白 Paypal IPN，而一旦我弄明白了，我就觉得好傻。