System.Xml.XmlDocument (class)

Methods

`CloneNode`	duplicates a node
`CreateAttribute`	Creates a `System.Xml.XmlAttribute` with the given name
`CreateCDataSection`	Creates a `System.Xml.XmlCDataSection` with the given data
`CreateComment`	Creates a `System.Xml.XmlComment`
`CreateDefaultAttribute`	Creates a `System.Xml.XmlDocumentFragment`
`CreateDocumentFragment`
`CreateDocumentType`	Creates a `System.Xml.XmlDocumentType` instance
`CreateElement`	Creates a `System.Xml.XmlElement` instance
`CreateEntityReference`
`CreateNavigator`	Creates a `System.Xml.XPath.XPathNavigator` instance to navigate this document.
`CreateNode`	Creates a `System.Xml.XmlNode` instance
`CreateProcessingInstruction`
`CreateSignificantWhitespace`
`CreateTextNode`	Creates a `System.Xml.XmlTextNode` instance
`CreateWhitespace`
`CreateXmlDeclaration`
`GetElementById`
`GetElementsByTagName`
`ImportNode`
`Load`
`LoadXml`
`ReadNode`
`Save`	Format an XML document and save it
`Validate`
`WriteContentTo`
`WriteTo`

See also the methods of the base class XmlNode.

Example: modify an XML document

The following simple PowerShell script tries to demonstrate how an XML document can be modifed using System.Xml.XmlDocument:

set-strictMode -version latest

function get-or-create-elem-with-id($doc, $id) {

   $elem = $doc.SelectSingleNode("/rt/item[@id='$id']")

   if ($elem -eq $null) {
      $elem = $doc.CreateElement('elem')
      $elem.SetAttribute('id', $id)

      $null = $doc.SelectSingleNode('/rt').AppendChild($elem)
   }

   return $elem
}


function create-val-if-not-exists($elem, $valName, $doc) {

   if ($elem.SelectSingleNode($valName) -eq $null) {

      $val = $doc.CreateElement($valName)
      $val.InnerText = 'created'

      $null = $elem.AppendChild($val)
   }
}


[xml] $doc = new-object xml
$doc.Load("$pwd/orig.xml")

foreach ($id in 'foo', 'bar', 'baz') {

   $elem = get-or-create-elem-with-id $doc  $id

   create-val-if-not-exists $elem 'valOne' $doc
   create-val-if-not-exists $elem 'valTwo' $doc
}

$doc.Save("$pwd/modified.xml")
type modified.xml

Github repository .NET-API, path: /System/Xml/XmlDocument/_modify/modify.ps1

orig.xml

This is the orig.xml file that is modified by the script:

<rt>

   <item id="foo">
      <valOne>foo 1</valOne>
      <valTwo>foo 2</valTwo>
   </item>

   <item id="baz">
      <valOne>baz 1</valOne>
   </item>

</rt>

Github repository .NET-API, path: /System/Xml/XmlDocument/_modify/orig.xml

modified.xml

The result of running the script is:

<rt>
  <item id="foo">
    <valOne>foo 1</valOne>
    <valTwo>foo 2</valTwo>
  </item>
  <item id="baz">
    <valOne>baz 1</valOne>
    <valTwo>created</valTwo>
  </item>
  <elem id="bar">
    <valOne>created</valOne>
    <valTwo>created</valTwo>
  </elem>
</rt>