根据Url地址生成静态页完成后中文出现乱码是怎么回事呀

//根据Url地址生成静态页保持
        protected void Button2_Click(object sender, EventArgs e)
        {
            Encoding code = Encoding.GetEncoding("utf-8");
            StreamReader sr = null;
            StreamWriter sw = null;
            string str = null;

            //读取远程路径
            WebRequest temp = WebRequest.Create(txtUrl.Text.Trim());
            WebResponse myTemp = temp.GetResponse();
            sr = new StreamReader(myTemp.GetResponseStream(), code);
            //读取
            try
            {
                sr = new StreamReader(myTemp.GetResponseStream(), code);
                str = sr.ReadToEnd();

            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                sr.Close();
            }
            string fileName = DateTime.Now.ToString("yyyyMMddHHmmss") + ".htm";

            //写入
            try
            {
                sw = new StreamWriter(Server.MapPath("htm/") + fileName, false, code);
                sw.Write(str);
                sw.Flush();

            }
            catch (Exception ex)
            {
                throw ex;
            }
            finally
            {
                sw.Close();
                Response.Write("恭喜<a href=htm/" + fileName + " target=_blank>" + fileName + "</a>已经生成，保存在htm文件夹下！");
            }

        }
    }