Unattended.xml : remove a child item containing a value

Question

Hi all,
I have in a section :
        <component name="Microsoft-Windows-Setup" processorArchitecture="amd64" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
            <DiskConfiguration>
                <Disk wcm:action="add">
                    <CreatePartitions>
                       <CreatePartition wcm:action="add">
                               <Order>1</Order>
                               <Type>Primary</Type>
                               <Size>350</Size>
                               <Extend>false</Extend>
                          </CreatePartition>
                          <CreatePartition wcm:action="add">
                               <Order>2</Order>
                               <Type>EFI</Type>
                               <Size>100</Size>
                               <Extend>false</Extend>
                          </CreatePartition>
                          <CreatePartition wcm:action="add">
                               <Order>3</Order>
                               <Type>MSR</Type>
                               <Size>128</Size>
                          </CreatePartition>
                          <CreatePartition wcm:action="add">
                               <Order>4</Order>
                               <Type>Primary</Type>
                               <Size>64000</Size>
                               <Extend>true</Extend>
                           </CreatePartition>
                     </CreatePartitions>
I load the contents of the Xml in the $Xml Variable
To remove a <CreatePartition></CreatePartition> block, I do the following :
# Delete Partition 3 & 4 of the Template
$tmp = $Xml.unattend.settings[1].component[1].DiskConfiguration.disk[0].CreatePartitions.CreatePartition[3] # MSR UEFI
[void] $Xml.unattend.settings[1].component[1].DiskConfiguration.disk[0].CreatePartitions.RemoveChild($tmp)
$tmp = $Xml.unattend.settings[1].component[1].DiskConfiguration.disk[0].CreatePartitions.CreatePartition[2] # Windows UEFI
[void] $Xml.unattend.settings[1].component[1].DiskConfiguration.disk[0].CreatePartitions.RemoveChild($tmp)
And if works great
Now, I would like to remove in the second CreationPartition section the line
                               <Size>100</Size>
I tried :
$tmp = $Xml.unattend.settings[1].component[1].DiskConfiguration.disk[0].CreatePartitions.CreatePartition[1].Size
But it returns the string 100 instead of an object on <Size>100</Size>
I also tried
$tmp = $Xml.unattend.settings[1].component[1].DiskConfiguration.disk[0].CreatePartitions.CreatePartition[1]$tmp.RemoveAttribute("Size")
But it does not remove "Size"
$tmp
action : add
Order : 2
Type : EFI
Size : 100
Extend : false
Could you help me to find the correct syntax.
Thanks
ML

Answer 1

Here is a complete example with the namespace:
$txt=@'
<?xml version="1.0" ?>
<unattend xmlns="urn:schemas-microsoft-com:unattend">
<settings>
<component name="Microsoft-Windows-Setup" processorArchitecture="amd64" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<DiskConfiguration>
<Disk wcm:action="add">
<CreatePartitions>
<CreatePartition wcm:action="add">
<Order>1</Order>
<Type>Primary</Type>
<Size>350</Size>
<Extend>false</Extend>
</CreatePartition>
<CreatePartition wcm:action="add">
<Order>2</Order>
<Type>EFI</Type>
<Size>100</Size>
<Extend>false</Extend>
</CreatePartition>
<CreatePartition wcm:action="add">
<Order>3</Order>
<Type>MSR</Type>
<Size>128</Size>
</CreatePartition>
<CreatePartition wcm:action="add">
<Order>4</Order>
<Type>Primary</Type>
<Size>64000</Size>
<Extend>true</Extend>
</CreatePartition>
</CreatePartitions>
</Disk>
</DiskConfiguration>
</component>
</settings>
</unattend>
$xml=[xml]$txt
$nsmgr=New-Object System.Xml.XmlNamespaceManager($xml.NameTable)
$nsmgr.AddNamespace('df','urn:schemas-microsoft-com:unattend')
$parent=$xml.SelectSingleNode('//df:CreatePartition[./df:Order[text()=2]]',$nsmgr)
$size=$xml.SelectSingleNode('//df:CreatePartition/df:Size[../df:Order[text()=2]]',$nsmgr)
$parent.RemoveChild($size)
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