服务器端之间采用http接口调数据时的Cookie传值问题

        public static string UrlGet(string url)
        {
            string responseContent = "";
            string cookieValue = getCurrentUserSessionID();
            HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(url);
            httpWebRequest.Timeout = 10 * 1000;
            httpWebRequest.Method = "GET";
           // httpWebRequest.ContentType = "application/json";
            httpWebRequest.Headers.Add("Accept-Language", "zh-cn,zh;q=0.5");
            httpWebRequest.Headers.Add("Accept-Charset", "gb2312,utf-8;q=0.7,*;q=0.7");
            httpWebRequest.Headers.Add("cookie", "ASPNETSESSIONGUID="+cookieValue+";");
            httpWebRequest.Headers.Set("Pragma", "no-cache");
            httpWebRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; QQWubi 133; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; CIBA; InfoPath.2)";
            HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
            using (Stream responseStream = httpWebResponse.GetResponseStream())
            {
                using (StreamReader responseReader = new StreamReader(responseStream, Encoding.UTF8))
                {
                    responseContent = responseReader.ReadToEnd();
                }
            }

            return responseContent;
        }

        private static string getCurrentUserSessionID()
        {
            HttpCookie cookie = HttpContext.Current.Request.Cookies["ASPNETSESSIONGUID"];
            if (cookie == null)
            {
                return null; //new UserLoginException();
            }

            return cookie.Value;//"4A914D3D87FE96AE5CF5050A80485FC1";
        }