PowerShell Cmdlet Deep Dive: New-Alias

Welcome back to Wahmans PowerShell Blog! Today we are going to cover a simple yet powerful cmdlet that can streamline your command-line workflows — New-Alias.

What is New-Alias?

The New-Alias cmdlet allows you to create a new alias for a PowerShell cmdlet or function. Aliases are shorthand names that you can use instead of typing out full cmdlet names, making your scripting more efficient. According to Microsoft:

New-Alias: Creates a new alias.

Aliases are great for repeated use, easing the transition from other shells, or even just customizing your own PowerShell experience.

Usage Syntax

New-Alias [-Name] <string> [-Value] <string> [-Description <string>] [-Force] [-Passthru] [-Scope <string>]

Examples from Beginner to Advanced

1. Beginner: Create an Alias for Get-ChildItem

If you’re used to Linux commands like ls, you can map ls to Get-ChildItem.

New-Alias -Name ls -Value Get-ChildItem

Now you can simply type ls in PowerShell to list directory contents!

2. Intermediate: Alias for a Custom Function

Let’s say you have a function called Get-SystemInfo that gathers system information. You can create an alias for it.

function Get-SystemInfo {
  Get-ComputerInfo | Select-Object OSName, CsTotalPhysicalMemory
}

New-Alias -Name sysinfo -Value Get-SystemInfo

Now just type sysinfo to execute your custom function.

3. Advanced: Temporarily Overriding Built-in Alias

PowerShell comes with built-in aliases like gc for Get-Content. You can override it temporarily.

New-Alias -Name gc -Value Get-Clipboard -Force

This changes gc to paste from clipboard instead. Be aware that this only lasts for your session unless you add it to your profile.

4. Advanced: Scoped Aliases

You can set scope for your alias, ensuring it only exists in a specific scope (e.g., a script or a function scope).

function Test-AliasScope {
  New-Alias -Name whoami -Value whoami.exe -Scope Local
  whoami
}

Test-AliasScope
whoami  # This will only work inside the function scope

By defining the scope, your alias won’t interfere with global aliases outside the function.

Wrapping Up

The New-Alias cmdlet can save you time, help with cross-platform comfort (like mapping bash commands), or even streamline your workflow by mapping frequently used cmdlets and functions. Whether you’re scripting occasionally or living in PowerShell daily, custom aliases are a handy feature to have in your toolbox.

Happy scripting, and I will see you in the next post!