通过应用程序读取网页信息的时候，通常需要抓取网页的数据，但是有一个问题就是很多网页需要登录后才能够获得页面数据，那么就需要保存当前的cookie，在.NET中可以使用CookieContainer 对象来保存登录后的Cookie信息，每次发送数据的时候加上Cookie信息，就可以解决这个问题了。

#region 同步通过POST方式发送数据
        /// <summary>
        /// 通过POST方式发送数据
        /// </summary>
        /// <param name="Url">url</param>
        /// <param name="postDataStr">Post数据</param>
        /// <param name="cookie">Cookie容器</param>
        /// <returns></returns>
        public string SendDataByPost(string Url,string postDataStr,ref CookieContainer cookie)
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
            if (cookie.Count == 0)
            {
                request.CookieContainer = new CookieContainer();
                cookie = request.CookieContainer;
            }
            else
            {
                request.CookieContainer = cookie;
            }

request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";
            request.ContentLength = postDataStr.Length;
            Stream myRequestStream = request.GetRequestStream();
            StreamWriter myStreamWriter = new StreamWriter(myRequestStream, Encoding.GetEncoding("gb2312"));
            myStreamWriter.Write(postDataStr);
            myStreamWriter.Close();

HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            Stream myResponseStream = response.GetResponseStream();
            StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.GetEncoding("utf-8"));
            string retString= myStreamReader.ReadToEnd();
            myStreamReader.Close();
            myResponseStream.Close();

return retString;
        }
        #endregion

#region 同步通过GET方式发送数据
        /// <summary>
        /// 通过GET方式发送数据
        /// </summary>
        /// <param name="Url">url</param>
        /// <param name="postDataStr">GET数据</param>
        /// <param name="cookie">GET容器</param>
        /// <returns></returns>
        public string SendDataByGET(string Url, string postDataStr, ref CookieContainer cookie)
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url +( postDataStr == "" ? "" : "?") + postDataStr);
            if (cookie.Count == 0)
            {
                request.CookieContainer = new CookieContainer();
                cookie = request.CookieContainer;
            }
            else
            {
                request.CookieContainer = cookie;
            }

request.Method = "GET";
            request.ContentType = "text/html;charset=UTF-8";
           
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            Stream myResponseStream = response.GetResponseStream();
            StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.GetEncoding("utf-8"));
            string retString = myStreamReader.ReadToEnd();
            myStreamReader.Close();
            myResponseStream.Close();

return retString;
        }
        #endregion