HttpWebRequest 有关 uri 的编码有关问题

HttpWebRequest 有关 uri 的编码问题
利用 http analyzer 抓包的URL 
http://www.qidian.com/BookReader/DivAuthorTipping.aspx?bookId=1321104&authorId=1648617&authorName=%u71d5%u5f52%u6881

我的代码如下
                string myUri = "http://www.qidian.com/BookReader/DivAuthorTipping.aspx?bookId=1321104&authorId=1648617&authorName=%u71d5%u5f52%u6881";
                HttpWebRequest myHttpWebRequest12 = (HttpWebRequest)WebRequest.Create(myUri);
                if (IsNeedProxy)
                    myHttpWebRequest12.Proxy = proxy;
                myHttpWebRequest12.Timeout = 500000;
                myHttpWebRequest12.Accept = "image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/msword, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/x-silverlight, */*";
                myHttpWebRequest12.Referer = strUrl + strUser2;
                myHttpWebRequest12.Headers.Add("Accept-Language", "zh-cn");
                myHttpWebRequest12.Headers.Add("Accept-Encoding", "gzip, deflate"); //add by King Lao
                myHttpWebRequest12.Headers.Add("Cache-Control", "no-cache");
                myHttpWebRequest12.ContentType = "application/x-www-form-urlencoded ";
                myHttpWebRequest12.ContentLength = indata1.Length;
                myHttpWebRequest12.Method = "POST";
                myHttpWebRequest12.CookieContainer = myCookieContainer;
                myHttpWebRequest12.UserAgent = "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR 2.0.50727; MAXTHON 2.0)";
                Stream myRequestStream12 = myHttpWebRequest12.GetRequestStream();
                StreamWriter myStreamWriter12 = new StreamWriter(myRequestStream12, Encoding.GetEncoding("gb2312"));
                myStreamWriter12.Write(indata1);
                myStreamWriter12.Close();
                myRequestStream12.Close();
                HttpWebResponse myHttpWebResponse12 = (HttpWebResponse)myHttpWebRequest12.GetResponse();