C#抓取网页乱码

public static void GetWebContent(string url)

        {

            try

            {

                

                HttpWebRequest myHttpWebRequest = (HttpWebRequest)WebRequest.Create(url);

                //myHttpWebRequest.SendChunked = true;

                //myHttpWebRequest.TransferEncoding = "gb2312";

                HttpWebResponse myHttpWebResponse = (HttpWebResponse)myHttpWebRequest.GetResponse();

                myHttpWebRequest.ContentType = "text/html";

                //Console.WriteLine("The encoding method used is: " + myHttpWebResponse.ContentEncoding);

                Console.WriteLine("字符编码:" + myHttpWebResponse.CharacterSet);

                Stream webStream = myHttpWebResponse.GetResponseStream();

                string encoding = myHttpWebResponse.CharacterSet;

                //经过大量测试发现.NET会将gb2312的编码格式识别为ISO-8859-1，故作此处理

                encoding = (encoding == "ISO-8859-1") ? "gb2312" : encoding;

                //获取的内容是否属于文本

                char seperator = '/';

                String contenttype = myHttpWebResponse.ContentType;

                // 返回 'text' 如果文本类型是'text/html.

                String maintype = contenttype.Substring(0, contenttype.IndexOf(seperator));

                // 只保存内容为'text'类型的网页，不保存示图片等其他文件

                if (String.Compare(maintype, "text") == 0)

                {

                    Console.WriteLine("\n Content type is 'text'.");

                    StreamReader sw = new StreamReader(webStream, System.Text.Encoding.GetEncoding(encoding));

                    Console.WriteLine("网页内容：");

                    StringBuilder sb = new StringBuilder();

                    while (sw.Peek() >= 0)

                    {

                        string strWebContent = sw.ReadLine();

                        sb.Append(strWebContent);

                    }

                    sw.Close();

                    sw.Dispose();

                    webStream.Close();



                    Console.WriteLine(sb.ToString());

                }

                else

                {

                    Console.Write("网页内容不是文本无法显示!");

                }

            }

            catch (Exception ex)

            {

                Console.WriteLine("Error:" + ex.Message);

            }



        }