Stream stream = new MemoryStream(Encoding.UTF8.GetBytes(
  "GET /gsscoder/httphelpers HTTP/1.1\r\n" +
  "Content-Type: text/html; q=0.9, text/plain\r\n\r\n"));

bool result = await HttpParser.ParseMessageAsync(stream, (method, uri, version) =>
  {
    Debug.WriteLine(method);
    Debug.WriteLine(uri);
    Debug.WriteLine(version);
  },
  (header, value) => 
    Debug.WriteLine(header + " " + value);

// When parsing a response, just name heading-line lambda parameters:
// version, code and reason.
// For the body: just read remaining bytes from the stream.