XML writing problem.. Encoding Fixing

MemoryStream ms = new MemoryStream();
XmlTextWriter writer = new XmlTextWriter(ms, System.Text.ASCIIEncoding.UTF8);
writer.Indentation = 3;
writer.Formatting = Formatting.Indented;
writer.WriteProcessingInstruction("xml", "version=\"1.0\" encoding=\"utf-8\"");
writer.WriteStartElement("Report");
writer.WriteAttributeString("xmlns", null, "http://schemas.microsoft.com/sqlserver/reporting/2003/10/reportdefinition");//Writing namespace
writer.WriteAttributeString("xmlns", "rd", null, "http://schemas.microsoft.com/SQLServer/reporting/reportdesigner");//Writing namespace


Or You can use StringBuilder class object like below
StringBuilder sb = new StringBuilder();
StringWriter sw = new StringWriter(sb);