How to iterate through XML in Powershell?

Question

I have this XML document in a text file:

<?xml version="1.0"?>
<Objects>
  <Object Type="System.Management.Automation.PSCustomObject">
    <Property Name="DisplayName" Type="System.String">SQL Server (MSSQLSERVER)</Property>
    <Property Name="ServiceState" Type="Microsoft.SqlServer.Management.Smo.Wmi.ServiceState">Running</Property>
  </Object>
  <Object Type="System.Management.Automation.PSCustomObject">
    <Property Name="DisplayName" Type="System.String">SQL Server Agent (MSSQLSERVER)</Property>
    <Property Name="ServiceState" Type="Microsoft.SqlServer.Management.Smo.Wmi.ServiceState">Stopped</Property>
  </Object>
</Objects>

I want to iterate through each object and find the DisplayName and ServiceState. How would I do that? I've tried all kinds of combinations and am struggling to work it out.

I'm doing this to get the XML into a variable:

[xml]$priorServiceStates = Get-Content $serviceStatePath;

where $serviceStatePath is the xml file name shown above. I then thought I could do something like:

foreach ($obj in $priorServiceStates.Objects.Object)
{
    if($obj.ServiceState -eq "Running")
    {
        $obj.DisplayName;
    }
}

And in this example I would want a string outputted with SQL Server (MSSQLSERVER)

Your XML appears to be serialized directly from in memory objects. Is there a reason you wouldn't just deserialize them back into memory? — jpmc26
– jpmc26, Commented Jan 22, 2019 at 18:26

Eric Pohl · Accepted Answer · 2016-11-21 17:34:13Z

55

PowerShell has built-in XML and XPath functions. You can use the Select-Xml cmdlet with an XPath query to select nodes from XML object and then .Node.'#text' to access node value.

[xml]$xml = Get-Content $serviceStatePath
$nodes = Select-Xml "//Object[Property/@Name='ServiceState' and Property='Running']/Property[@Name='DisplayName']" $xml
$nodes | ForEach-Object {$_.Node.'#text'}

Or shorter

[xml]$xml = Get-Content $serviceStatePath
Select-Xml "//Object[Property/@Name='ServiceState' and Property='Running']/Property[@Name='DisplayName']" $xml |
  % {$_.Node.'#text'}

edited Nov 21, 2016 at 17:34

Eric Pohl

2,3421 gold badge21 silver badges31 bronze badges

answered Aug 29, 2013 at 11:28

mswietlicki

1,47312 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

mswietlicki Over a year ago

I've added some explanation.

zneak Over a year ago

You can also navigate the document using the familiar property syntax: ($xml.Objects.Object | ? { $_.ServiceState -eq "Running" }).DisplayName

Anthony Horne Over a year ago

The explicit conversion to [xml] did it for me. Without the conversion, it returns the xml (as string) and the parsing does not work. No error - of course.

alex Over a year ago

What version of Powershell was this introduced in?

zett42 Over a year ago

Get-Content is the wrong way to load XML, because it doesn't respect the encoding attribute of the XML header. Most of the time we get lucky, only because many XML documents are UTF-8 encoded, which happens to be the default encoding used by Get-Content nowadays. Still it's wrong, for more details see stackoverflow.com/a/65264118/7571258

js2010 · Accepted Answer · 2019-01-22 18:18:57Z

You can also do it without the [xml] cast. (Although xpath is a world unto itself. https://www.w3schools.com/xml/xml_xpath.asp)

$xml = (select-xml -xpath / -path stack.xml).node
$xml.objects.object.property

Or just this, xpath is case sensitive. Both have the same output:

$xml = (select-xml -xpath /Objects/Object/Property -path stack.xml).node
$xml


Name         Type                                                #text
----         ----                                                -----
DisplayName  System.String                                       SQL Server (MSSQLSERVER)
ServiceState Microsoft.SqlServer.Management.Smo.Wmi.ServiceState Running
DisplayName  System.String                                       SQL Server Agent (MSSQLSERVER)
ServiceState Microsoft.SqlServer.Management.Smo.Wmi.ServiceState Stopped

Collectives™ on Stack Overflow

How to iterate through XML in Powershell?

2 Answers 2

5 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

5 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related