如何在C＃中从此响应中提取并获取值

Question

Here is my code:

private void button1_Click(object sender, EventArgs e)
    {
        var process = new com.globalpay.certapia.GlobalPayments();
        var response = process.ProcessCreditCard("xxxxxx", "xxxxxx", "Sale",
            textBox1.Text, textBox2.Text, "", "", textBox3.Text, "",
            "", "", "", "", "");

        MessageBox.Show("RespMSG: " + response.RespMSG
            + "\nMessage: " + response.Message
            + "\nAuthCode: " + response.AuthCode
            + "\nPNRef: " + response.PNRef
            + "\nHostCode: " + response.HostCode
            + "\nCVResultTXT: " + response.GetCVResultTXT
            + "\nCommercialCard: " + response.GetCommercialCard
            + "\nExtData: " + response.ExtData);
    }

The output goes like this:

In the part of ExtData I got confused I do not know how can I extract those values like get the value of CardType, BatchNum, MID, TransID.

How can I possibly extract those values?

Any advice or suggestion how can I achieve this will be a big help. Thanks!

base on the doc of api:

 <?xml version="1.0" encoding="utf-8" ?>
<Response xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="GlobalPayments">
<Result>0</Result>
<RespMSG>Approved</RespMSG>
<Message>AP</Message>
<AuthCode>000014</AuthCode>
<PNRef>564286</PNRef>
<HostCode>0032</HostCode>
<GetCVResultTXT>Service Not Requested</GetCVResultTXT>
<GetCommercialCard>False</GetCommercialCard>
<ExtData>InvNum=1234567900,CardType=MasterCard,BatchNum=0011<BatchNum>0011
</BatchNum><ReceiptData><MID>4910354</MID><Trans_Id>MCC1421250315
</Trans_Id></ReceiptData></ExtData>
</Response>

Answer 1

This seems to be case of incorrectly formatted response. This is quite common with these kind of webservices. Don't expect it to get better any time soon.

You simply need to brute-force the parsing and hope they don't change it or it is changed based on what kind of response you get.

General algorithm would be:

1. Separate the 2 different parts
   • Coma-delimitered, equality-valued part
   • XML-formated part
   • This could be done, maybe by finding first index of '<' and splitting the string into 2 in this place
2. Parse the 2 parts with different algorithm. In first case, the parsing shouldn't be a problem. Just split along ',' and '=' and you get key-value pairs. In second case, you should use some XML parsing library to help you. Again, you get bunch of key-value pairs.
3. Put all key-value pairs into a string/string dictionary.

Answer 2

Using LINQ would be the easiest way, assuming the response is a string or something you can turn into a string:

// XDocument.Parse will load a string into the XDocument object.
XDocument xDoc = XDocument.Parse(response);
// XNamespace is required in order to parse the document.
XNamespace ns = "GlobalPayments";

var resp = (from x in xDoc.Descendants(ns + "ExtData")
            select new
            {
                ExtData = x.Value,
                BatchNum = x.Element(ns + "BatchNum").Value,
                MID = x.Element(ns + "MID").Value,
                TransID = x.Element(ns + "TransID").Value
            }).SingleOrDefault();

You would then have an anonymous type ( resp ) with the following propertries:

resp.ExtData = "InvNum=1234567900,CardType=MasterCard,BatchNum=0011"
resp.BatchNum = "0011"
resp.MID = "4910354"
resp.TransID = "MCC1421250315"

You could then use normal String.Split operations on ExtData to get the data from that string you need.

Not the prettiest solution, but sometimes you have to brute force methods. Adopt and modify to suit your needs/tastes.

Answer 3

You need to extract them manually by using String.IndexOf..), and then String.SubString(..) etc

var cardType = data.Substring(data.IndexOf("<BatchNum>"), data.IndexOf("</BatchNum>") - data.IndexOf("<BatchNum>"));

With some exceptions handling code of course...