How to edit root element value of XML using XML writer in C#

check with this links http://www.dotnetperls.com/xmlwriter
http://social.msdn.microsoft.com/Forums/vstudio/en-US/3c3d462b-b6fb-4051-b1c7-d4bd49bd463a/c-write-and-append-xml-elements-using-xmltextwriter-or-any-other-way-which-is-faster-and-preferable?forum=csharpgeneral
http://stackoverflow.com/questions/3247312/root-element-missing-creating-xmldocument-using-xmltextwriter
http://stackoverflow.com/questions/3380033/xml-root-node-not-closed