How to append records in exist XMl file?

[Matrix]

Greetings

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() //????????

[Malek]

that's the whole idea (XmlTextWriter has to validate content as XML ...), so
using XmlDoxument makes sense ...
"Matrix" <co*****@163.com> wrote in message
news:eE****************@TK2MSFTNGP10.phx.gbl...

Greetings

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() //????????

[Oleg Tkachenko [MVP]]

Matrix 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?

XML document is tree-like structure, so to append records one has to
rearrange structure, what hardly possible in file on disk.
The only case when XmlWriter can append data to XML file is when it's
not XML document, but XML fragment (XML document with more than single
root element). That's common pattern for writing XML-based log files. As
there is no single root element rule, you can merely append records to
the end of file:

<log time="..." event="..."/>
<log time="..." event="..."/>
<log time="..." event="..."/>

Above is XML fragment, which is easily appendable and can be incpropated
into another document via external entity or just read using
XmlTextReader, which happily supports reading of XML fragments.
See sample at http://www.tkachenko.com/blog/archives/000053.html

--
Oleg Tkachenko [XML MVP, XmlInsider]
http://blog.tkachenko.com