LiveCodingChat.HttpHelper.CreatePostData C# (CSharp) Метод

        public static byte[] CreatePostData(Dictionary<string,string> postData)
        {
            StringBuilder bld = new StringBuilder ();
            foreach (KeyValuePair<string,string> pair in postData) {
                if (bld.Length != 0)
                    bld.Append("&");
                if (pair.Value == "")
                    bld.Append (HttpUtility.UrlEncode(pair.Key));
                else
                    bld.Append (HttpUtility.UrlEncode(pair.Key) + "=" + HttpUtility.UrlEncode(pair.Value));
            }
            return System.Text.Encoding.UTF8.GetBytes (bld.ToString ());
        }

        private void LoginGithub(string username, string password, string data, ref CookieContainer cookies)
        {
            //POST login data
            Dictionary <string, string> postData = new Dictionary <string, string> ();
            HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create("https://github.com/session");

            request.UserAgent       = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; .NET CLR 1.0.3705)";
            request.CookieContainer = cookies;
            request.Method          = "POST";
            request.ContentType     = "application/x-www-form-urlencoded";

            postData.Add("utf8", "\u2713");
            postData.Add("authenticity_token", HtmlHelper.getAttribute(HtmlHelper.getSingleElement(data, "<input name=\"authenticity_token\""), "value"));
            postData.Add("login", username);
            postData.Add("password", password);
            postData.Add("return_to", HtmlHelper.getAttribute(HtmlHelper.getSingleElement(data, "<input id=\"return_to\" name=\"return_to\""), "value"));

            byte[] postBuild = HttpHelper.CreatePostData(postData);
            request.ContentLength = postBuild.Length;
            request.GetRequestStream().Write(postBuild, 0, postBuild.Length);

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();

            using (System.IO.StreamReader sr = new System.IO.StreamReader(response.GetResponseStream())) {
                data = sr.ReadToEnd();
            }

            if (LoginCompleted != null)
            {
                LoginCompleted(this, new LoginEventArgs(data, cookies));
            }
        }