Editing an XML document in C# -

i'm new c#. attempting edit spreadsheetxml 2003 document adding bunch of nodes different worksheets in it. here example of structure:

<workbook>  <worksheet ss:name="contact">   <table>    <column />    <row />   </table>  </worksheet>  <worksheet ss:name="facility">   <table>    <column />    <row />   </table>  </worksheet> </workbook> 

what need load xml , insert new nodes @ places. i'm pretty sure know how create new xelement nodes under need (there's plenty of tutorials online that). i'm having trouble finding how find node , add nodes under it. far i've got:

xelement xmldoc = xelement.load(environment.getfolderpath(environment.specialfolder.applicationdata) + "\\autodesk\\revit\\addins\\2013\\cobiev2.4template.xml"); 

so, how find "facility" worksheet , add new row under table node in it? need able in such way @ end of routine can save xmldoc file out file system.

---- update ----- i'm not getting work. revised code , beginning of actual xml below.

<?xml version="1.0"?> <?mso-application progid="excel.sheet"?> <workbook xmlns="urn:schemas-microsoft-com:office:spreadsheet"  xmlns:o="urn:schemas-microsoft-com:office:office"  xmlns:x="urn:schemas-microsoft-com:office:excel"  xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet"  xmlns:html="http://www.w3.org/tr/rec-html40"> <worksheet ss:name="contact">   <names>    <namedrange ss:name="_filterdatabase" ss:refersto="=contact!r1c1:r1c19"     ss:hidden="1"/>   </names>   <table ss:expandedcolumncount="19" ss:expandedrowcount="1" x:fullcolumns="1"    x:fullrows="1" ss:defaultcolumnwidth="49.5" ss:defaultrowheight="15">    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="209.25"/>    <column ss:styleid="s1251" ss:autofitwidth="0" ss:width="209.25"/>    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="160.5"/>    <column ss:styleid="s1251" ss:autofitwidth="0" ss:width="119.25"/>    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="129"/>    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="82.5"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="165"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="129.75"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="45"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="45"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="129"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="66"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="107.25"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="198"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="65.25"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="72"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="45"/>    <column ss:styleid="s1253" ss:autofitwidth="0" ss:width="62.25"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="45"/>    <row ss:height="93">     <cell ss:styleid="s1254"><data ss:type="string">email</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/><namedcell       ss:name="contact.name"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">createdby</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">createdon</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">category</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">company</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">phone</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalsystem</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalobject</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalidentifier</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">department</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">organizationcode</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">givenname</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">familyname</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">street</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">postalbox</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">town</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">stateregion</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1255"><data ss:type="string">postalcode</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">country</data><namedcell       ss:name="_xlnm._filterdatabase_4"/><namedcell ss:name="_filterdatabase"/></cell>    </row>   </table>   <worksheetoptions xmlns="urn:schemas-microsoft-com:office:excel">    <pagesetup>     <header x:margin="0.51180555555555551"/>     <footer x:margin="0.51180555555555551"/>    </pagesetup>    <print>     <validprinterinfo/>     <horizontalresolution>300</horizontalresolution>     <verticalresolution>300</verticalresolution>    </print>    <tabcolorindex>43</tabcolorindex>    <zoom>81</zoom>    <freezepanes/>    <frozennosplit/>    <splithorizontal>1</splithorizontal>    <toprowbottompane>1</toprowbottompane>    <splitvertical>1</splitvertical>    <leftcolumnrightpane>1</leftcolumnrightpane>    <activepane>0</activepane>    <panes>     <pane>      <number>3</number>     </pane>     <pane>      <number>1</number>     </pane>     <pane>      <number>2</number>     </pane>     <pane>      <number>0</number>      <activerow>0</activerow>      <activecol>0</activecol>     </pane>    </panes>    <protectobjects>false</protectobjects>    <protectscenarios>false</protectscenarios>    <enableselection>noselection</enableselection>   </worksheetoptions>   <autofilter x:range="r1c1:r1c19"    xmlns="urn:schemas-microsoft-com:office:excel">   </autofilter>  </worksheet>  <worksheet ss:name="facility">   <names>    <namedrange ss:name="_filterdatabase" ss:refersto="=facility!r1c1:r1c22"     ss:hidden="1"/>   </names>   <table ss:expandedcolumncount="22" ss:expandedrowcount="1" x:fullcolumns="1"    x:fullrows="1" ss:defaultcolumnwidth="49.5" ss:defaultrowheight="15">    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="46.5"/>    <column ss:styleid="s1251" ss:autofitwidth="0" ss:width="174"/>    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="162"/>    <column ss:styleid="s1251" ss:autofitwidth="0" ss:width="96"/>    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="116.25"/>    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="45.75"/>    <column ss:styleid="s1251" ss:autofitwidth="0" ss:width="45.75"/>    <column ss:styleid="s1251" ss:autofitwidth="0" ss:width="78"/>    <column ss:styleid="s1251" ss:autofitwidth="0" ss:width="69"/>    <column ss:styleid="s1251" ss:autofitwidth="0" ss:width="45.75"/>    <column ss:styleid="s1247" ss:autofitwidth="0" ss:width="230.25"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="179.25"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="54.75"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="156"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="45.75"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="154.5"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="60.75"/>    <column ss:styleid="s1252" ss:autofitwidth="0" ss:width="156"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="116.25" ss:span="1"/>    <column ss:index="21" ss:styleid="s1248" ss:autofitwidth="0" ss:width="45.75"/>    <column ss:styleid="s1248" ss:autofitwidth="0" ss:width="74.25"/>    <row ss:height="124.5">     <cell ss:styleid="s1254"><data ss:type="string">name</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/><namedcell       ss:name="facility.name"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">createdby</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">createdon</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">category</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">projectname</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">sitename</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">linearunits</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">areaunits</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">volumeunits</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">currencyunit</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">areameasurement</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalsystem</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalprojectobject</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalprojectidentifier</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalsiteobject</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalsiteidentifier</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalfacilityobject</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">externalfacilityidentifier</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">description</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">projectdescription</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">sitedescription</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>     <cell ss:styleid="s1254"><data ss:type="string">phase</data><namedcell       ss:name="_xlnm._filterdatabase_7"/><namedcell ss:name="_filterdatabase"/></cell>    </row>   </table>   <worksheetoptions xmlns="urn:schemas-microsoft-com:office:excel">    <pagesetup>     <header x:margin="0.51180555555555551"/>     <footer x:margin="0.51180555555555551"/>    </pagesetup>    <print>     <validprinterinfo/>     <horizontalresolution>300</horizontalresolution>     <verticalresolution>300</verticalresolution>    </print>    <tabcolorindex>43</tabcolorindex>    <zoom>81</zoom>    <freezepanes/>    <frozennosplit/>    <splithorizontal>1</splithorizontal>    <toprowbottompane>1</toprowbottompane>    <splitvertical>1</splitvertical>    <leftcolumnrightpane>1</leftcolumnrightpane>    <activepane>0</activepane>    <panes>     <pane>      <number>3</number>     </pane>     <pane>      <number>1</number>     </pane>     <pane>      <number>2</number>     </pane>     <pane>      <number>0</number>      <activerow>20</activerow>     </pane>    </panes>    <protectobjects>false</protectobjects>    <protectscenarios>false</protectscenarios>    <enableselection>noselection</enableselection>   </worksheetoptions>   <autofilter x:range="r1c1:r1c22"    xmlns="urn:schemas-microsoft-com:office:excel">   </autofilter>  </worksheet> </workbook>  xdocument xmldoc = xdocument.load(environment.getfolderpath(environment.specialfolder.applicationdata) + "\\autodesk\\revit\\addins\\2013\\cobiev2.4template.xml");              /* ---- facility info ---- */             var workbook = xmldoc.root.element("workbook");             if (workbook != null)             {                 var element = (from e in workbook.elements("worksheet")                                e.attribute("ss:name").value == "facility"                                select e).firstordefault();                  if (element != null)                 {                     taskdialog.show("worksheet", "found facility");                     var tablenode = element.element("table");                     if (tablenode != null)                     {                         taskdialog.show("table", "found table");                         tablenode.add(new xelement("row",                             new xelement("cell",                                 new xelement("data", rdoc.projectinformation.name)                                     )                         ));                     }                 }             }             else             {                 taskdialog.show("workbook", "workbook not found");             } 

the "workbook" isn't being found. not understanding this, because seems should work.

how find node node = xmldoc.element

and check it's attribute node.attributes

then, add nodes node.add