Query Help - wmiobject win32_product filter items from text file

Question

I've been working on a simple script to read the win32_product off a remote PC, which is working fine. However, I would like the query to ignore some common applications on my domain. I've been building a list of apps and their IdentifyingNumber and putting the IdentifyingNumber into a txt file. I load the text file into a variable with the script and I'm trying to figure out how to get the query to filter each item in the variable...so I have this::

$PC = Read-Host "What is target workstation..."
$logfile = "d:\$PC.txt"
$ignore = [IO.File]::ReadAllText("D:\INCOMING\AppListing\ignore.txt")
get-wmiobject -class win32_product -computer $PC | where {$_.IdentifyingNumber -notlike       $ignore} | Select Name, IdentifyingNumber | sort-object Name | export-csv $logfile -encoding "unicode"

However, this is not filtering at all, not even the first or last item from the txt file. I used write-host $ignore to verify it is loading the items...but I am at a lost as to how to make this work. Perhaps a foreach loop? I can't find anything about putting a foreach loop into a where filter though...

Thanks for the assistance...

Answer 1

If the file is like this:

aRandomId
anotherRandonId
...

with one id on each line and nothing else, then try this using -notlike with wildcards on the ends. Ex:

$PC = Read-Host "What is target workstation..."
$logfile = "d:\$PC.txt"
$ignore = [IO.File]::ReadAllText("D:\INCOMING\AppListing\ignore.txt")
get-wmiobject -class win32_product -computer $PC | where { $ignore -notlike "*$($_.identifyingnumber)*" } |
Select Name, IdentifyingNumber | sort-object Name | export-csv $logfile -encoding "unicode"

You could also read your file as an array using ReadAllLines like you would have had to do if you wanted to use a foreach-loop or -notcontains. Ex:

$PC = Read-Host "What is target workstation..."
$logfile = "d:\$PC.txt"
$ignore = [IO.File]::ReadAllLines("D:\INCOMING\AppListing\ignore.txt")
get-wmiobject -class win32_product -computer $PC | where { $ignore -notcontains $_.identifyingnumber } |
Select Name, IdentifyingNumber | sort-object Name | export-csv $logfile -encoding "unicode"

Answer 2

$prods = Compare-Object -ReferenceObject (Get-Content $file) -DifferenceObject ((Get-WmiObject -Class Win32_Product -Computer $computer).IdentifyingNumber) -PassThru

Compare-Object is a great Cmdlet.