POWERSHELL Task Scheduler passing variables inside -Argument - powershell

Question

Good afternoon,
I am very new to Powershell and am trying to achieve the following:
Loop through a folder directory
Set the folder name as a variable
Create a Task
Pass the variable (declared in Step 2) as the required parameter for the -File being called in the Task Action
Get-ChildItem -Path C:\Users\Paul\Documents\RSYNC -Directory -Recurse |ForEach-Object {
$FolderName = $_.name
$taskName = 'My Powershell Task_' + $FolderName
# Create Action
$Action = New-ScheduledTaskAction -Execute 'powershell.exe' -Argument '-File "C:\Users\Paul\Documents\RSYNC\Get-LatestAppLog.ps1" -name "$FolderName"'
# Create Trigger
$Trigger = New-ScheduledTaskTrigger -Daily -At 12:35am
# Create Settings
$Settings = New-ScheduledTaskSettingsSet
# Create Task
$Task = New-ScheduledTask -Action $Action -Trigger $Trigger -Settings $Settings
# Register Task
Register-ScheduledTask -TaskName $taskName -InputObject $Task -User 'username' -Password 'password'
}
The tasks are created as desired, however, the problem is that inside the $Action step, instead of passing the folder name inside the $FolderName variable, it is simply passing $FolderName as a string (I hope that makes sense).
How can I correctly pass the folder name to the PowerShell script being called?

Answer 1

Your immediate problem was to expect the reference to variable $FolderName to be expanded (interpolated) inside a verbatim PowerShell string literal, '...':
Only "..." strings (double-quoted) perform string interpolation in PowerShell: see this answer for an overview of PowerShell's expandable strings (interpolating strings) and this answer for an overview of PowerShell string literals in general.
While swapping the use of quotation marks - using "..." for the outer quoting and '...' for the embedded quoting in order to get interpolation may situationally work - depending on the target program or API - it does not work in the context of Task Scheduler.
For command lines in Task Scheduler - and generally on Windows from outside PowerShell - you must use "..." quoting for the embedded strings too, which therefore requires escaping " as `" ("" would work too).
The reason is that PowerShell doesn't treat ' characters as having syntactic function when its CLI is called from the outside, such as from Task Scheduler, cmd.exe, or the Windows Run dialog (WinKey-R). For instance, if the path passed to -File were 'C:\Users\Paul\Documents\RSYNC\Get-LatestAppLog.ps1', the ' chars. would be interpreted as part of the path.
Specifically:
$Action = New-ScheduledTaskAction -Execute 'powershell.exe' -Argument `
"-File `"C:\Users\Paul\Documents\RSYNC\Get-LatestAppLog.ps1`" -name `"$FolderName`""
Note that you could simplify the quoting with the use of an expandable here-string; the embedded " then do not require escaping:
$Action = New-ScheduledTaskAction -Execute 'powershell.exe' -Argument #"
-File "C:\Users\Paul\Documents\RSYNC\Get-LatestAppLog.ps1" -name "$FolderName"
"#

Answer 2

Thank you Theo and Abraham Zinala. Both suggested to swap the double and single quotes and that worked perfectly.