In the previous tip we explained how you can use a separate new and fresh PowerShell to retrieve all default variables. When you examine these variables closely, you will discover that still some PowerShell variables are missing.
Here is a slightly modified version called Get-BuiltInPSVariable that includes all reserved PowerShell variables:
function Get-BuiltInPSVariable($Name='*') { # create a new PowerShell $ps = [PowerShell]::Create() # get all variables inside of it $null = $ps.AddScript('$null=$host;Get-Variable') $ps.Invoke() | Where-Object Name -like $Name # dispose new PowerShell $ps.Runspace.Close() $ps.Dispose() }
To not miss out on any built-in PowerShell variable, this approach uses AddScript() instead of AddCommand(), and issues more than one command. Some PowerShell variables are created only after at least one command has run.
You can now dump all PowerShell built-in variables, or search for selected:
PS> Get-BuiltInPSVariable -Name *pref* Name Value ---- ----- ConfirmPreference High DebugPreference SilentlyContinue ErrorActionPreference Continue InformationPreference SilentlyContinue ProgressPreference Continue VerbosePreference SilentlyContinue WarningPreference Continue WhatIfPreference False
