PowerShell Cheat Sheet / Quick Reference

cheatsheet.ps1

Get-Command                                               # Retrieves a list of all the commands available to PowerShell
                                                          # (native binaries in $env:PATH + cmdlets / functions from PowerShell modules)

Get-Help                                                  # Get all help topics
Get-Help -Name about_Variables                            # Get help for a specific about_* topic (aka. man page)
Get-Help -Name Get-Command                                # Get help for a specific PowerShell function
Get-Help -Name Get-Command -Parameter Module              # Get help for a specific parameter on a specific command

###################################################
# Flow Control Statements
###################################################

if (1 -eq 1) { }                                          # Do something if 1 is equal to 1

do { 'hi' } while ($false)                                # Loop while a condition is true (always executes at least once)

while ($false) { 'hi' }                                   # While loops are not guaranteed to run at least once
while ($true) { }                                         # Do something indefinitely
while ($true) { if (1 -eq 1) { break } }                  # Break out of an infinite while loop conditionally

for ($i = 0; $i -le 10; $i++) { Write-Host $i }           # Iterate using a for..loop
foreach ($item in (Get-Process)) { }                      # Iterate over items in an array

###################################################
# Variables
###################################################


$a = 0                                                    # Initialize a variable
[int] $a = 'Trevor'                                       # Initialize a variable, with the specified type (throws an exception)
[string] $a = 'Trevor'                                    # Initialize a variable, with the specified type (doesn't throw an exception)

Get-Command -Name *varia*                                 # Get a list of commands related to variable management

Get-Variable                                              # Get an array of objects, representing the variables in the current and parent scopes 
Get-Variable | ? { $PSItem.Options -contains 'constant' } # Get variables with the "Constant" option set
Get-Variable | ? { $PSItem.Options -contains 'readonly' } # Get variables with the "ReadOnly" option set

New-Variable -Name FirstName -Value Trevor
New-Variable FirstName -Value Trevor -Option Constant     # Create a constant variable, that can only be removed by restarting PowerShell
New-Variable FirstName -Value Trevor -Option ReadOnly     # Create a variable that can only be removed by specifying the -Force parameter on Remove-Variable

Remove-Variable -Name firstname                           # Remove a variable, with the specified name
Remove-Variable -Name firstname -Force                    # Remove a variable, with the specified name, that has the "ReadOnly" option set

###################################################
# Functions
###################################################

# A PowerShell Advanced Function, with all three blocks declared: BEGIN, PROCESS, END
function Do-Something {
  [CmdletBinding]()]
  param ()
  begin { }
  process { }
  end { }
}

###################################################
# Working with Modules
###################################################

Get-Command -Name *module* -Module mic*core                 # Which commands can I use to work with modules?

Get-Module -ListAvailable                                   # Show me all of the modules installed on my system (controlled by $env:PSModulePath)
Get-Module                                                  # Show me all of the modules imported into the current session

$PSModuleAutoLoadingPreference = 0                          # Disable auto-loading of installed PowerShell modules, when a command is invoked

Import-Module -Name NameIT                                  # Explicitly import a module, from the specified filesystem path or name (must be present in $env:PSModulePath)
Remove-Module -Name NameIT                                  # Remove a module from the scope of the current PowerShell session

New-ModuleManifest                                          # Helper function to create a new module manifest. You can create it by hand instead.

New-Module -Name trevor -ScriptBlock {                      # Create an in-memory PowerShell module (advanced users)
  function Add($a,$b) { $a + $b } }

New-Module -Name trevor -ScriptBlock {                      # Create an in-memory PowerShell module, and make it visible to Get-Module (advanced users)
  function Add($a,$b) { $a + $b } } | Import-Module

###################################################
# Module Management
###################################################

Get-Command -Module PowerShellGet                           # Explore commands to manage PowerShell modules

Find-Module -Tag cloud                                      # Find modules in the PowerShell Gallery with a "cloud" tag
Find-Module -Name ps*                                       # Find modules in the PowerShell Gallery whose name starts with "PS"

Install-Module -Name NameIT -Scope CurrentUser -Force       # Install a module to your personal directory (non-admin)
Install-Module -Name NameIT -Force                          # Install a module to your personal directory (admin / root)
Install-Module -Name NameIT -RequiredVersion 1.9.0          # Install a specific version of a module

Uninstall-Module -Name NameIT                               # Uninstall module called "NameIT", only if it was installed via Install-Module

Register-PSRepository -Name <repo> -SourceLocation <uri>    # Configure a private PowerShell module registry
Unregister-PSRepository -Name <repo> -SourceLocation uri    # Deregister a PowerShell Repository