C#的post请求 捕获错误代码的内容

public string Query(stringqueryString)
        {
            try{
                HttpWebRequest request =(HttpWebRequest)HttpWebRequest.Create(AOPResource.LVSRequestURL);
                request.Method = "POST";
                UTF8Encoding encoding = newUTF8Encoding();
                byte[] byteArray =encoding.GetBytes(queryString);

                request.ContentType = "application/x-www-form-urlencoded";
                request.ContentLength =byteArray.Length;

                Stream requestStream =request.GetRequestStream();
                requestStream.Write(byteArray, 0, byteArray.Length);
                WebResponse response =request.GetResponse();
                Stream responseStream =response.GetResponseStream();
                StreamReader sr = newStreamReader(responseStream);

                string result =sr.ReadToEnd();
                requestStream.Close();
                sr.Close();
                responseStream.Close();
                returnresult;
            }
            catch(WebException e)
            {
                using (WebResponse response =e.Response)
                {
                    HttpWebResponse httpResponse =(HttpWebResponse)response;
                    Console.WriteLine("Error code: {0}", httpResponse.StatusCode);
                    using (Stream data =response.GetResponseStream())
                    using (var reader = newStreamReader(data))
                    {
                        string text =reader.ReadToEnd();
                        throw newException(text);
                    }
                }
            }
        }