System.Xml.XmlTextWriter.WriteCData C# (CSharp) Method

        public override void WriteCData(string text) {
            try {
                AutoComplete(Token.CData);
                if (null != text && text.IndexOf("]]>", StringComparison.Ordinal) >= 0) {
                    throw new ArgumentException(Res.GetString(Res.Xml_InvalidCDataChars));
                }
                textWriter.Write("<![CDATA[");

                if (null != text) {
                    xmlEncoder.WriteRawWithSurrogateChecking(text);
                }
                textWriter.Write("]]>");
            }
            catch {
                currentState = State.Error;
                throw;
            }
        }

        protected void Page_Load(object sender, System.EventArgs e)
        {
            Response.ContentType = "text/xml";
            Response.ContentEncoding = Encoding.UTF8;

            string mediaType = Request.QueryString["type"];
            string mediaID = Request.QueryString["id"];
            string wa = "waStartStream";

            TextWriter tw = new StreamWriter(Response.OutputStream, Encoding.UTF8);
            XmlWriter xw = new XmlTextWriter(tw);

            //start doc
            xw.WriteStartDocument();

            //start root
            xw.WriteStartElement("root");

            //go
            xw.WriteStartElement("go");
            xw.WriteAttributeString("to", wa);
            xw.WriteEndElement();
            //end go

            //start title
            xw.WriteStartElement("title");
            xw.WriteAttributeString("set", wa);
            xw.WriteEndElement();
            //end title

            //start dest
            xw.WriteStartElement("destination");
            xw.WriteAttributeString("mode", "replace");
            xw.WriteAttributeString("zone", wa);
            xw.WriteAttributeString("create", "true");
            xw.WriteEndElement();
            //end dest

            //start data
            xw.WriteStartElement("data");
            xw.WriteCData(DoCountdown(mediaID, mediaType));
            xw.WriteEndElement();
            //end data

            //start script
            xw.WriteStartElement("script");
            xw.WriteCData("startCountdown(21)");
            xw.WriteEndElement();
            //end script

            //end root
            xw.WriteEndElement();

            //end doc
            xw.WriteEndDocument();
            xw.Close();
        }