asp.net动态生成xml编码问题

动态生成xml内容，显示到页面上，在ie中查看，无法显示xml页，提示内容应该是编码有问题，不知道怎么解决

代码大概如下

XmlDocument xmldoc = new XmlDocument();

          //声明
            XmlDeclaration xmldecl;
            xmldecl = xmldoc.CreateXmlDeclaration("1.0", "UTF-8", null); ;
            xmldecl.Encoding = "GB2312";

             //加入一个根元素
            XmlElement xmlelem = xmldoc.CreateElement("", "YFBGLIST", "");
            xmldoc.AppendChild(xmlelem);
            xmldoc.InsertBefore(xmldecl, xmlelem);


          //加入另外一个元素
            for (int i = 0; i < rsint; i )
            {
                string[] k = new string[k2];
                k = rs[i].Split('@');
                XmlNode root = xmldoc.SelectSingleNode("YFBGLIST");//查找<Employees>
                XmlElement xe1 = xmldoc.CreateElement("YFBG");//创建一个<Node>节点
                    XmlElement xesub1 = xmldoc.CreateElement("yfbgtitle");
                xesub1.InnerText = k[0];

                xe1.AppendChild(xesub1);//添加到<Node>节点中
                XmlElement xesub2 = xmldoc.CreateElement("researcher");
                xesub2.InnerText = k[3];
                xe1.AppendChild(xesub2);
                XmlElement xesub3 = xmldoc.CreateElement("url");
                xesub3.InnerText = k[4];
                XmlElement xesub4 = xmldoc.CreateElement("content");
                xesub4.InnerText = k[5];
                xe1.AppendChild(xesub3);

                root.AppendChild(xe1);//
            }
                     MemoryStream stream = new MemoryStream();
            XmlTextWriter writer = new XmlTextWriter(stream, new System.Text.UTF8Encoding(false));
            writer.Formatting = Formatting.Indented;

xmldoc.Save(writer);

            StreamReader sr = new StreamReader(stream, new System.Text.UTF8Encoding(false));
            stream.Position = 0;
            string XMLString = sr.ReadToEnd();
            return XMLString;

sr.Close();
stream.Close();

哆啦的时光机