How to write values to XML file with Powershell

Question

I'm new to Powershell and need to write some data to an existing XML file. I found a lot of simple XML examples which I can't adopt to the file I need to write to. What I'm trying to do is to write to:

Bld_version.build
Bld_version.major
Bld_version.minor
Bld_version.patch

in this File:

<?xml version='1.0' encoding='UTF-8'?>
<Project Type="Project" LVVersion="20008000">
    <Property Name="NI.LV.All.SourceOnly" Type="Bool">true</Property>
    <Property Name="NI.Project.Description" Type="Str"></Property>
    <Item Name="My Computer" Type="My Computer">
        <Property Name="server.app.propertiesEnabled" Type="Bool">true</Property>
        <Property Name="server.control.propertiesEnabled" Type="Bool">true</Property>
        <Item Name="private" Type="Folder">
            <Item Name="Type Defs" Type="Folder">
                <Item Name="App Data.ctl" Type="VI" URL="../App Data.ctl"/>
                <Item Name="App States.ctl" Type="VI" URL="../App States.ctl"/>
                <Item Name="Check Options States.ctl" Type="VI" URL="../Check Options States.ctl"/>
                <Item Name="LV versions.ctl" Type="VI" URL="../LV versions.ctl"/>
            </Item>
            <Item Name="Build Help Text.vi" Type="VI" URL="../Build Help Text.vi"/>
            <Item Name="Check Folder Permission.vi" Type="VI" URL="../Check Folder Permission.vi"/>
            <Item Name="Check Options.vi" Type="VI" URL="../Check Options.vi"/>
            <Item Name="Convert Files.vi" Type="VI" URL="../Convert Files.vi"/>
            <Item Name="Get Vipb Path.vi" Type="VI" URL="../Get Vipb Path.vi"/>
            <Item Name="Prepare Temp Directory.vi" Type="VI" URL="../Prepare Temp Directory.vi"/>
            <Item Name="Save for Previous Version (lib).vi" Type="VI" URL="../Save for Previous Version (lib).vi"/>
            <Item Name="Save for Previous Version (proj).vi" Type="VI" URL="../Save for Previous Version (proj).vi"/>
            <Item Name="Save for Previous Version (vi).vi" Type="VI" URL="../Save for Previous Version (vi).vi"/>
        </Item>
        <Item Name="public" Type="Folder">
            <Item Name="Vip Tool.vi" Type="VI" URL="../Vip Tool.vi"/>
        </Item>
        <Item Name="res" Type="Folder">
            <Item Name="vip.ico" Type="Document" URL="../vip.ico"/>
        </Item>
        <Item Name="Build Specifications" Type="Build">
            <Item Name="vip-tool" Type="EXE">
                <Property Name="Bld_version.build" Type="Int">20</Property>
                <Property Name="Bld_version.major" Type="Int">1</Property>
                <Property Name="Bld_version.minor" Type="Int">1</Property>
                <Property Name="Bld_version.patch" Type="Int">1</Property>
            </Item>
        </Item>
    </Item>
</Project>

I can't even read the four values cause I can't figure out a way to "navigate" to the data. Creating the object and loading the file is pretty straight forward but reading/ writing the data under the vip-tool node is a different beast.

PS U:> $var = New-Object System.XML.XMLDocument
PS U:> $var = Get-Content -Path "C:Vip Build Tool.lvproj" -ErrorAction "Stop"
PS U:> $var.Project."Item"."Item"

Name                 Type
----                 ----
private              Folder
public               Folder
res                  Folder
Build Specifications Build

Maybe someone can help me with this, there is obviously something basic I still don't understand about how to get to the data or write to it.

question from:https://stackoverflow.com/questions/65885210/how-to-write-values-to-xml-file-with-powershell

Answer 1

Another way is to use the dotted object notation, where you have the advantage that it works case-insensitive as opposed to XPath:

$path = "C:Vip Build Tool.lvproj"
$xml = New-Object System.XML.XMLDocument
$xml.Load($path)

$buildSpecs = ($xml.Project.Item.Item | Where-Object { $_.Name -eq "Build Specifications" }).Item.Property
($buildSpecs | Where-Object { $_.Name -eq "Bld_version.build" }).InnerText = 123
($buildSpecs | Where-Object { $_.Name -eq "Bld_version.major" }).InnerText = 2
($buildSpecs | Where-Object { $_.Name -eq "Bld_version.minor" }).InnerText = 3
($buildSpecs | Where-Object { $_.Name -eq "Bld_version.patch" }).InnerText = 4

$xml.Save($path)