Passing multiple values to a single PowerShell script parameter

Question

I have a script to which I pass server name(s) in $args.

This way I can do stuff to this (these) server(s) using foreach:

.\script.ps1 host1 host2 host3  foreach ($i in $args) {     Do-Stuff $i } 

I'd like to add a named optional parameter called vlan. I've tried:

Param(     [string]$vlan )  foreach ($i in $args) {     Write-Host $i } Write-Host $vlan 

It works if you pass a -vlan parameter but if you don't then the script auto assigns the last server name to $vlan.

So, how can you pass single or multiple parameters plus an optional named parameter to a PowerShell script?

Ideally, here are valid examples:

.\script.ps1 host1 .\script.ps1 host1 host2 host3 .\script.ps1 host1 host2 -vlan office 

Answer 1

The easiest way is probably to use two parameters: One for hosts (can be an array), and one for vlan.

param([String[]] $Hosts, [String] $VLAN) 

Instead of

foreach ($i in $args) 

you can use

foreach ($hostName in $Hosts) 

If there is only one host, the foreach loop will iterate only once. To pass multiple hosts to the script, pass it as an array:

myScript.ps1 -Hosts host1,host2,host3 -VLAN 2 

...or something similar.

Answer 2

One way to do it would be like this:

 param(        [Parameter(Position=0)][String]$Vlan,        [Parameter(ValueFromRemainingArguments=$true)][String[]]$Hosts     ) ... 

This would allow multiple hosts to be entered with spaces.