How to append records in exist XMl file?

[Matrix]

I want to append records in a XML file,I use XMLTextWriter,but i found it
only create a XML file,not append records in exist XML file.why?
-------------------------------------------------
XmlTextWriter myXmlTextWrite = new XmlTextWriter(@"C:\myconfig.xml");
myXmlTextWrite.WriteStartDocument();
myXmlTextWrite.WriteStartElement("Record");
myXmlTextWrite.WriteStartElement("Topic");
myXmlTextWrite.WriteString(XMLTopic);
myXmlTextWrite.WriteEndElement();
myXmlTextWrite.WriteEndElement(); //end Record
myXmlTextWrite.WriteEndDocument();
myXmlTextWrite.Flush();
myXmlTextWrite.Close();
=================================================
i should use XMLDocument?
------------------------------
XmlDocument xmldoc= new XmlDocument();
xmldoc.Load(@"C:\myconfig.xml");
xmldoc.DocumentElement.AppendChild() //????????

[Thomas Johansen]

Hi,

The XmlTextWriter was not designed to append data to existing documents -
you should, as you suggested yourself, use XmlDocument if you want to append
xml data to an existing document.

--
Regards,
Thomas Johansen (aka. Aylar)
Matrix <co*****@163.com> wrote:

I want to append records in a XML file,I use XMLTextWriter,but i
found it only create a XML file,not append records in exist XML
file.why? -------------------------------------------------
XmlTextWriter myXmlTextWrite = new XmlTextWriter(@"C:\myconfig.xml");
myXmlTextWrite.WriteStartDocument();
myXmlTextWrite.WriteStartElement("Record");
myXmlTextWrite.WriteStartElement("Topic");
myXmlTextWrite.WriteString(XMLTopic);
myXmlTextWrite.WriteEndElement();
myXmlTextWrite.WriteEndElement(); //end Record
myXmlTextWrite.WriteEndDocument();
myXmlTextWrite.Flush();
myXmlTextWrite.Close();
=================================================
i should use XMLDocument?
------------------------------
XmlDocument xmldoc= new XmlDocument();
xmldoc.Load(@"C:\myconfig.xml");
xmldoc.DocumentElement.AppendChild() //????????