HttpWebRequest hwreq= (HttpWebRequest)HttpWebRequest.Create(sUrl);
...其它信息
hwreq.Headers.Add("Accept-Encoding", "gzip"); //打包
hwreq.AutomaticDecompression = DecompressionMethods.GZip; //解包
hwreq.GetResponse();
原文：http://www.cnblogs.com/Charles-xu/p/4913623.html