Is it possible to pass a variable or function powershell -File $file instead of constant string powershell -File 'C:\Script\test.ps1' as the file parameter?

The following command works fine

C:\Script>PowerShell.exe -ExecutionPolicy Bypass -windowstyle hidden "$file = Get-ChildItem -Path C:\Script -Include test.ps1 -Recurse | Select-Object -ExpandProperty FullName"; Invoke-Item $file

but, if I change "Invoke-Item" with "-File" it doesn't work and I get an error Command:

C:\Script>PowerShell.exe -ExecutionPolicy Bypass -windowstyle hidden "$file = Get-ChildItem -Path C:\Script -Include test.ps1 -Recurse | Select-Object -ExpandProperty FullName"; -File $file

Error:

-File : Termine '-File' non riconosciuto come nome di cmdlet, funzione, programma eseguibile o file script. Controllare l'ortografia del nome o verificare che il percorso sia incluso e corretto, quindi
riprovare.
In riga:1 car:115
+ ... st.ps1 -Recurse | Select-Object -ExpandProperty FullName; -File $file
+                                                               ~~~~~
    + CategoryInfo          : ObjectNotFound: (-File:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

Is it possible to pass a variable or function powershell -File $file instead of constant string powershell -File 'C:\Script\test.ps1' as the file parameter?

The following command works fine

C:\Script>PowerShell.exe -ExecutionPolicy Bypass -windowstyle hidden "$file = Get-ChildItem -Path C:\Script -Include test.ps1 -Recurse | Select-Object -ExpandProperty FullName"; Invoke-Item $file

but, if I change "Invoke-Item" with "-File" it doesn't work and I get an error Command:

C:\Script>PowerShell.exe -ExecutionPolicy Bypass -windowstyle hidden "$file = Get-ChildItem -Path C:\Script -Include test.ps1 -Recurse | Select-Object -ExpandProperty FullName"; -File $file

Error:

-File : Termine '-File' non riconosciuto come nome di cmdlet, funzione, programma eseguibile o file script. Controllare l'ortografia del nome o verificare che il percorso sia incluso e corretto, quindi
riprovare.
In riga:1 car:115
+ ... st.ps1 -Recurse | Select-Object -ExpandProperty FullName; -File $file
+                                                               ~~~~~
    + CategoryInfo          : ObjectNotFound: (-File:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

• powershell

2 Answers 2

Use the invocation operator (&)!

Change:

Invoke-Item $file

to:

& $file

To ensure you only ever attempt to execute one script, use Select-Object's -First parameter:

$file = Get-ChildItem -Path C:\Script -Include test.ps1 -Recurse | Select-Object -ExpandProperty FullName -First 1; & $file

If you want to invoke multiple scripts, wrap each call in a ForEach-Object block:

Get-ChildItem -Path C:\Script -Include test.ps1 -Recurse | Select-Object -ExpandProperty FullName |ForEach-Object { & $_ }

The short answer is no—you cannot use a variable (or function) in place of a literal string for the -File parameter when launching PowerShell.exe. The -File switch is handled by the PowerShell executable itself before any of your inline script code (and thus any variable assignments) is executed.

Because -File is processed before the session starts, it cannot resolve any variables defined in the command string. If you need dynamic behavior, compute the file path first (outside of the PowerShell call) or use -Command where variable expansion is available.