Powershell - Environment Variable

About

environment variable in powershell

Type

Beside the session scope, an environment variable may be stored with the following scopes:

• User = user profile.
• Machine = computer as a whole,
• Process = restricted to a single process.

Management

Display all variables

Get-ChildItem Env:
# or
dir env:

Display One

$Env:os

Windows_NT

Get

the .NET Framework to return information about a particular environment variable:

[Environment]::GetEnvironmentVariable("Sample","User")

where:

• Sample is the name of the environment variable we want to retrieve
• and User, the type of environment variable.

Set

Create and/or set

Session-level

$env:TestVariable = "This is a test environment variable."

If PowerShell can’t find an environment variable named TestVariable it will automatically create the variable and assign it the specified value.

User-level or machine-level

You need to use the .NET Framework and the SetEnvironmentVariable method.

[Environment]::SetEnvironmentVariable("TestVariable", "Test value.", "User")

where:

• “User” makes TestVariable a user-level environment variable. Alternatively, we could have set this to “Machine” (machine-level) or “Process” (process-level).

Remove

• The Remove-Item cmdlet

Remove-Item Env:\TestVariable

• assigning the environment variable a null value

[Environment]::SetEnvironmentVariable("TestVariable",$null,"User")

Documentation / Reference

• Windows PowerShell Tip of the Week