C# httpRequest乱码

 因为返回的数据做了压缩

            //方式1
            //Stream stm = new System.IO.Compression.GZipStream(webresponse.GetResponseStream(), System.IO.Compression.CompressionMode.Decompress);

            ////return str;
            //using (stm)
            //{
            //    StreamReader reader = new StreamReader(stm, Encoding.UTF8);
            //    return reader.ReadToEnd();

            //}


            //方式2

            var stm = webresponse.GetResponseStream();
            using (stm)
            {
                var reader = new StreamReader(new GZipStream(stm, CompressionMode.Decompress), Encoding.GetEncoding("utf-8"));

                var bodys = reader.ReadToEnd();
                return bodys;
            }