Загрузка аудиозаписей в vk.com средствами vk api

 public static void loadToVK(string filePath)
        {
            string url = String.Format(@"https://api.vk.com/method/audio.getUploadServer.xml?access_token={0}", token);
            var xml = new XmlDocument();
            xml.Load(url);
            string serverUrl = xml.InnerText;
            serverUrl = serverUrl.Replace("&", "&");
            var bytes = File.ReadAllBytes(filePath);
            var cookies = new CookieContainer();
            ServicePointManager.Expect100Continue = false;
 
            var request = (HttpWebRequest)WebRequest.Create(serverUrl);
            request.CookieContainer = cookies;
            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";
            using (var requestStream = request.GetRequestStream())
            using (var writer = new StreamWriter(requestStream))
            {
                writer.Write(bytes);
            }
            string responseJSON;
            using (var responseStream = request.GetResponse().GetResponseStream())
            using (var reader = new StreamReader(responseStream))
            {
                responseJSON = reader.ReadToEnd();
            }
 
            Dictionary<string, string> info = ParseJson(responseJSON);
            url = String.Format(@"https://api.vk.com/method/audio.save.xml?server={0}&audio={1}&access_token={2}&hash={3}", info["server"], info["audio"], token, info["hash"]);
            xml = new XmlDocument();
            xml.Load(url);
            
        }

Dictionary<string, string> info = ParseJson(responseJSON);
            url = String.Format(@"https://api.vk.com/method/audio.save.xml?server={0}&audio={1}&access_token={2}&hash={3}", info["server"], info["audio"], token, info["hash"]);
            xml = new XmlDocument();
            xml.Load(url);