Using powershell to edit multiple XML files

Question

How can I get a list of multiple XML files from a specified directory and for each file add an element under the second root node using powershell?

Example: I want to add <LastName>SomeName</LastName> within the FIRST <Names> element:

<People>
  <Names>
      <FirstName>someFirstName</FirstName>
  </Names>
  <Names>
      <FirstName>myFirstName</FirstName>
      <Address>SomeAddress</Address>
  </Names>
</People>

Will become:

<People>
  <Names>
      <LastName>SomeName</LastName>
      <FirstName>someFirstName</FirstName>
  </Names>
  <Names>
      <FirstName>myFirstName</FirstName>
      <Address>SomeAddress</Address>
  </Names>
</People>

Answer 1

You can do it using CreateElement and AppendChild method

Get-ChildItem c:\temp\ *.xml | 
    % { 
        $xml      = [xml](Get-Content $_.fullname)
        $lastName = $xml.CreateElement('LastName')
        $lastName.PsBase.InnerText = 'SomeName'
        $null     = $xml.People.Names[0].AppendChild($lastName)
        $xml.Save($_.FullName)
    }

In case that you run PowerShell V2, you don't need to use property PsBase:

        $lastName.InnerText = 'SomeName'

There are for sure other ways, but this is one is quite easy.

---

In case that the node would be deeper in xml, you might use Xpath like this (both find first Names node):

$node = (Select-Xml -Xml $x -XPath '//Names[1]').Node
$node = (Select-Xml -Xml $x -XPath '//Names[position()=1]').Node