Парсинг сайта с javascript

 HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://www.magephonebook.com/search.php");

Cookie cookie = new Cookie(какие данные сюда вписать?);
 
request.CookieContainer = new CookieContainer();
request.CookieContainer.Add(cookie);

 string postData = "int=994&number=050+580+00+61";
            byte[] byteArray = Encoding.UTF8.GetBytes (postData);
           
            
            WebRequest request = WebRequest.Create("http://www.magephonebook.com/search.php");
            ((HttpWebRequest)request).CookieContainer = new CookieContainer();
            ((HttpWebRequest)request).CookieContainer = GetCookieContainer();
            request.Credentials = CredentialCache.DefaultCredentials;
            ((HttpWebRequest)request).UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36";
            request.Method = "POST";
            request.ContentLength = byteArray.Length;
            request.ContentType = "application/x-www-form-urlencoded; charset=UTF-8";
            
            Stream dataStream = request.GetRequestStream();
            // Write the data to the request stream.
            dataStream.Write(byteArray, 0, byteArray.Length);
            // Close the Stream object.
            dataStream.Close();
            // Get the response.
            WebResponse response = request.GetResponse();
            // Display the status.
            richTextBox1.Text += (((HttpWebResponse)response).StatusDescription);
            // Get the stream containing content returned by the server.
            dataStream = response.GetResponseStream();
            // Open the stream using a StreamReader for easy access.
            StreamReader reader = new StreamReader(dataStream);
            // Read the content.
            string responseFromServer = reader.ReadToEnd();
 
            
            richTextBox1.Text += responseFromServer;
            reader.Close();
            dataStream.Close();
            response.Close();

WebRequest _request = WebRequest.Create("http://www.magephonebook.com");
            //((HttpWebRequest)request).CookieContainer = new CookieContainer();
            ((HttpWebRequest)_request).CookieContainer = GetCookieContainer();
            _request.Credentials = CredentialCache.DefaultCredentials;
            ((HttpWebRequest)_request).UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36";
            _request.Method = "GET";
            //_request.ContentLength = byteArray.Length;
            _request.ContentType = "text/html; charset=UTF-8";
 
            Stream _dataStream = _request.GetRequestStream();
            // Write the data to the request stream.
            //dataStream.Write(byteArray, 0, byteArray.Length);
            // Close the Stream object.
            _dataStream.Close();
            // Get the response.
            WebResponse _response = request.GetResponse();
            // Display the status.
            richTextBox1.Text += (((HttpWebResponse)_response).StatusDescription);
            // Get the stream containing content returned by the server.
            dataStream = response.GetResponseStream();
            // Open the stream using a StreamReader for easy access.
            StreamReader _reader = new StreamReader(dataStream);
            // Read the content.
            string _responseFromServer = _reader.ReadToEnd();
 
 
            richTextBox1.Text += _responseFromServer;

 WebRequest _request = WebRequest.Create("http://www.magephonebook.com");
            //((HttpWebRequest)request).CookieContainer = new CookieContainer();
            ((HttpWebRequest)_request).CookieContainer = GetCookieContainer();
            _request.Credentials = CredentialCache.DefaultCredentials;
            ((HttpWebRequest)_request).UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36";
            _request.Method = "GET";
            //_request.ContentLength = byteArray.Length;
            _request.ContentType = "text/html; charset=UTF-8";
            WebResponse _response = _request.GetResponse();
            Stream _dataStream = _response.GetResponseStream();
            // Write the data to the request stream.
            //dataStream.Write(byteArray, 0, byteArray.Length);
            // Close the Stream object.
            
            // Open the stream using a StreamReader for easy access.
            StreamReader _reader = new StreamReader(_dataStream);
            // Read the content.
            string _responseFromServer = _reader.ReadToEnd();
 
 
            richTextBox1.Text += _responseFromServer;
            _reader.Close();
            _dataStream.Close();
           _response.Close();