Decode Form Urlencoded UTF8 in C#

Edit开发者_开发知识库 I'd misunderstood what was happening here.. there is a POST send, then receive back a result, then the URL string which I'm seeing here is part of the the query string... so I can't decode what this really is, as it is encoded by the payment gateway people and not me.

I'd like to decode a URL string

Here is the code:

private string SubmitXml(string InputXml)
    {
        string result = InputXml.ToString();

        HttpWebRequest webReq = (HttpWebRequest)WebRequest.Create(_WebServiceUrl);
        webReq.Method = "POST";

        byte[] reqBytes;

        reqBytes = System.Text.Encoding.UTF8.GetBytes(InputXml);
        webReq.ContentType = "application/x-www-form-urlencoded";
        webReq.ContentLength = reqBytes.Length;
        webReq.Timeout = 5000;
        Stream requestStream = webReq.GetRequestStream();
        requestStream.Write(reqBytes, 0, reqBytes.Length);
        requestStream.Close();

        HttpWebResponse webResponse = (HttpWebResponse)webReq.GetResponse();

Here is the InputXml:

 - <GenerateRequest>
  <PxPayUserId>KoruCareCHCH_Dev</PxPayUserId> 
  <PxPayKey>47d99ccdcae54816ecd78c9a80f8878c466a7ed829480e59d421cc4c456cbd93</PxPayKey> 
  <AmountInput>345.00</AmountInput> 
  <BillingId /> 
  <CurrencyInput>NZD</CurrencyInput> 
  <DpsBillingId /> 
  <DpsTxnRef /> 
  <EmailAddress /> 
  <EnableAddBillCard /> 
  <MerchantReference>43</MerchantReference> 
  <TxnData1 /> 
  <TxnData2 /> 
  <TxnData3 /> 
  <TxnType>Purchase</TxnType> 
  <TxnId>43</TxnId> 
  <UrlFail>http://localhost:1527/Auction/PurchaseTickets.aspx</UrlFail> 
  <UrlSuccess>http://localhost:1527/Auction/PurchaseTickets.aspx</UrlSuccess> 
  <Opt /> 
  </GenerateRequest>

Here is the URL

https://sec2.paymentexpress.com/pxpay/pxpay.aspx?userid=KoruCareCHCH_Dev&request=v5lK0D7j3qnGqQVnj3WThhuS5PoWwKhdLUXfnL1hiSzYzxzkKVtTbLKC49e0qerYoTAofoBXfkWHjJdtOEV1MrnEBZ3p9b-G5fTsS-sLqc76RhHOb8HTxtwe0EQ1kz1iCf2ExIgKRod-FPQTKf6XoTLLlQ4jhcrO7yQczrq1Hft5pB98LMJCdBX0FDnA5NV0ZGApR0NaCMy-xbpsVSsyTbSdmp03aiHpGXI4up2RxrBFhbiEOZKtpKkjUpqJ90UuoXmFwqTC5Pj0g1mx3VRV2ee358Tnu1_kuEID_RaP8sZNTVlAMY5-8qjB-u0dgM4ya8Faxxyw5AhyE=

Problem: How do I decode the URL request=blahblah back into XML

I'm doing this to try and prove what is contained in the URL string (it should be just like the XML above!)

Didn't have any luck decoding it so the URL might be wrong, but I used this code:

Uri uri = new Uri(...);
NameValueCollection query = HttpUtility.ParseQueryString(uri.Query);
string value = query["request"].Replace('-', '+').Replace('_', '/');
Debug.WriteLine(Convert.FromBase64String(value));

EDIT: In their docs they say it's encrypted.

You can use a regex, something like

var match = new Regex("request=(?<key>[^&]+)").Match(url);

and capture the request value in the named group. From there, hopefully you'd be able to decrypt the captured value.

No guarantees that the above regex is correct - I haven't tested it. It should at least point you in the right direction!