Advanced Windows PowerShell Scripting Video Training

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Advanced Windows PowerShell Scripting Video Training

Thursday, September 1, 2016

Avoid Using Property Names with Spaces

This is one that I have to reiterate often in my advanced class. 

So I’m looking over the forums on and I see an answer to a post that contains a custom object.  First of all, awesome.  This answer that was provided returned an object to the PowerShell Pipeline.  The problem that I have with it is the properties have spaces in the names.  This makes reusability of this code more difficult.  Let’s look at the code that was provided.

$pc = Get-Content -Path C:\ps\names.txt
$results = @()
$results = foreach ($machine in $pc) {
    $computerName = (Get-WMIObject -class Win32_ComputerSystem -computername $machine).name
    $osInfo= Get-WMIObject -Class Win32_Operatingsystem -ComputerName $machine
    $getip = ([version](Test-Connection $machine -Count 1).IPV4Address.IPAddressToString).Build
    $desc = (Get-ADComputer $machine -Properties Description).description
    $ie = (Get-Command "\\$machine\c$\Program Files\Internet Explorer\iexplore.exe").Version

    PCName = $computerName
    'OS Version' = $osInfo.Version
    'OS Type' = $osInfo.Caption
    'AD Description' = $desc
    'IP vLan' = $getip
    'IE Version' = $ie

$results | export-csv -Path c:\ps\test1.csv

Again, this is not my code so it may look different with how I usually write.  Let’s read the results with Import-CSV.
PS C:\ps> Import-Csv -Path C:\ps\test1.csv

PCName         : LON-CL1
OS Version     : 10.0.10240
OS Type        : Microsoft Windows 10 Enterprise 2015 LTSB Evaluation
AD Description :
IP vLan        : 1
IE Version     : 11.0.10240.16384

Things do not really look all that bad.  The properties are very readable.  Now let’s pipe this object and use it.

Import-Csv -Path C:\ps\test1.csv |
    Select-Object -ExpandProperty OS Version

Select-Object : Property "OS" cannot be found.
At line:2 char:5
+     Select-Object -ExpandPropert OS Version
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidArgument: (@{PCName=LON-CL....0.10240.16384}:PSObject) [Select-Object], PSArgumentException
    + FullyQualifiedErrorId : ExpandPropertyNotFound,Microsoft.PowerShell.Commands.SelectObjectCommand

PowerShell is looking for a property called “OS”, not “OS Version”.  Remember that a space in a PowerShell command line is actually the delimiter between elements of the command.   You are actually try to pass “Version” as a positional parameter.  That is not going to work.

To fix this, you have to use the curly braces.
Import-Csv -Path C:\ps\test1.csv |
    Select-Object -ExpandProperty {OS Version}

PS C:\ps> Import-Csv -Path C:\ps\test1.csv |
    Select-Object -ExpandProperty {OS Version}


When I receive information from a source that uses spaces, I immediately pipe the information to Select-Object and get rid of the spaces.  This allows me to code without adding the extra curly braces into my code while the object is in the pipeline.

Import-Csv -Path C:\ps\test1.csv |
    Select-Object -Property PCName,
        @{N = 'OSVersion' ; E = {$_.{OS Version}}},
        @{N = 'OSType' ; E = {$_.{OS Type}}},
        @{N = 'ADDescription' ; E = {$_.{AD Description}}},
        @{N = 'IPvLan' ; E = {$_.{IP vLan}}},
        @{N = 'IEVersion' ; E = {$_.{IE Version}}}

PCName        : LON-CL1
OSVersion     : 10.0.10240
OSType        : Microsoft Windows 10 Enterprise 2015 LTSB Evaluation
ADDescription :
IPvLan        : 1
IEVersion     : 11.0.10240.16384

Now moving forward, I do not need to add any extra curly braces.

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