Acting on every 100 elements of an array - powershell

Question

I am using Get-ADComputer to return all the computers in Active Directory.
We intend to call the DELL Warranty web-service API and retrieve warranty information for each computer.
The DELL Warranty web-service takes a pipe separated list of service tags, maximum 100, and we have 1483 computers ...
So I need to act on every 100 elements of the array populated by my code, but am having trouble.
clear-host
$Counter=0
$ServiceTag::Empty
$ServiceTagsMasterList=#()
(Get-ADComputer `
-properties OperatingSystem -filter {(operatingsystem -like "*Windows 7*")} `
|Where-Object {$_.name -like "*-*"}`
|Where-Object {$_.name -NotLike "V7-*"})`
| Select -Exp Name|ForEach-Object{
$ServiceTag = $_.substring(3) #remove w7- l7- etc....
if ($ServiceTag.Length -eq "7"){
#write-host "service tag:" $ServiceTag
$ServiceTagsMasterList += $ServiceTag + ','
$Counter+=1
}
}
write-host $ServiceTagsMasterList.length, $Counter, $Counter % 100
write-host $ServiceTagsMasterList
I am having trouble getting the Mod right - I expect $Counter % 100 to return 14 with remainder 83, but the output is 1483 % 100
I need to be able to call the DELL Warranty api for each block of 100 service tags, so I can either do it like that or perhaps split the array?
What's the best approach?

Answer 1

gpunktschmitz already mentioned whats wrong in your code. This is how your batch could look like:
$computer = Get-ADComputer -properties OperatingSystem -filter {(operatingsystem -like "*Windows 7*")} |
Where-Object {$_.name -like "*-*"} |
Where-Object {$_.name -NotLike "V7-*"} |
Select-Object -Expand
for ($i = 0; $i -lt $computer.length; $i+=100)
{
$computer | Select-Object -Skip $i -First 100 | ForEach-Object {
# your code here
}
}
Here an example with your 1483 computers:
$computer = 1 .. 1483 | ForEach-Object { "DellPc$($_)" }
for ($i = 0; $i -lt $computer.length; $i+=100)
{
$computer | Select-Object -Skip $i -First 100 | ForEach-Object {
Write-Host "batch: $i computer: $_"
}
}

Answer 2

you have to write it like this to be calculated:
write-host $ServiceTagsMasterList.length, $Counter, $($Counter % 100)
and % is the remainder not modulo
http://www.madwithpowershell.com/2016/11/powershell-modulus-operator-is.html