PowerShell script parameters not parsed correctly

Question

I have a simple script which does not work:

Param([string] $Input, [string] $Output)
Write-Host $Input
Write-Host $Output

The $Input parameter does not get printed:

PS> .\Get-Parameters.ps1 "First" "Second"

Second

If I rename $Input to $Joe the script works fine. $Input is not a reserved name.

What is going on? I am perplexed.

Did you read help about_Automatic_Variables?
– Ocaso Protal
Commented Nov 5, 2012 at 14:18 — Ocaso Protal, Commented Nov 5, 2012 at 14:18

CB. · Accepted Answer · 2012-11-05 14:17:16Z

2

PowerShell's $input is an automatic variable:

basically $input in an enumerator which provides access to the actual pipeline.

Reading about $input

answered Nov 5, 2012 at 14:17

CB.

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See about_Automatic_Variables and Automatic Variables
– sourcenouveau
Commented Nov 5, 2012 at 14:20
1

@emddudley The second link tell $Input is case-sensitive... really isn't it!!
– CB.
Commented Nov 5, 2012 at 14:27

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Webplanet TFS Consulting · Accepted Answer · 2012-11-05 14:21:38Z

1

$input in an enumerator which provides access to the pipeline you have.

reference here: $Input Gotchas

answered Nov 5, 2012 at 14:21

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2 Answers 2