title: how to issue a post request webclient under specific jwt context
body: <p>How can I issue a POST request under the context below using <em>webclient</em>?</p>
  
  <p>I am able to successfully authenticate and retrieve a <code>jwt</code> token from ADFS:</p>
  
  <pre><code>using (var client = new WebClient())
  {
      var data = Encoding.UTF8.GetBytes(rstXml);
      client.Headers.Add("Content-Type", "application/soap+xml; charset=utf-8");
      var responseData =
          client.UploadData($"https://{adfsServer}/adfs/services/trust/13/usernamemixed", data);
      var rstr = Encoding.UTF8.GetString(responseData);
      var xmlDoc = new XmlDocument();
      xmlDoc.LoadXml(rstr);
      var nsmgr = new XmlNamespaceManager(xmlDoc.NameTable);
      nsmgr.AddNamespace("wsse",
          "http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd");
      nsmgr.AddNamespace("wsu",
          "http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd");
      jwt = xmlDoc.SelectSingleNode("//wsse:BinarySecurityToken", nsmgr).InnerText; // JWT
   }
  </code></pre>
  
  <p>How do I issue a POST request under this same context?</p>