Visio-PowerShell-7.0-Quick-Reference-1.04.vsdx

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PowerShell 7.0 - Quick Reference

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Get-Help / Helpful Commands

Update-Help Updates local help files.

Get-Help Provides information on a command, it’s

parameters and available switches.

Get-Command Lists all commands. Can be filtered.

Get-Module Lists modules that are or can be loaded.

Get-Package Lists packages that are or can be loaded.

Get-PSRepository Lists available PowerShell Repositories

registered to the current user.

Get-Member Gets properties and methods of objects.

Get-PackageProviders Lists all loaded package provides.

(i.e. NuGet, PowerShellGet, etc.)

Show-Command List of available commands (GUI)

Comparison Operators

-eq equal -ne not equal

-lt less than -gt greater than

-ge greater than or equal -le less than or equal

-replace Replace string pattern

-like Returns true when string matches

-notlike Returns true when string does not match

-match Returns true when string matches regex

-notmatch Returns true when string does not match regex

-contains Returns true when reference value in a collection

-notcontains Returns true when reference value not in a collection

-in Returns true when test value contained in a collection

-notin

Returns true when test value not contained in a collection

Logical Operators

-and TRUE when both are TRUE

e.g. ‘(3 -eq 3) -and (1 -lt 3)’ is TRUE

-or TRUE when either is TRUE

e.g. (3 -lt 3) -or (2 -eq 2) is TRUE

-xor TRUE when only one is TRUE

e.g. (1 -eq 1) -xor (2 -eq 2)

FALSE

-not/! When a condition is not TRUE

e.g. -not (1 -eq 1) is FALSE

Other Operators

-split Splits a string

‘FirstName.LastName’ -Split ‘.’

# Results - ‘FirstName’ and ‘LastName’

-join Join’s multiple strings

‘John’,‘Smith’,‘IT’,‘Chicago’ -Join ‘,’

# Results - John,Smith,IT,Chicago

-replace Replaces a value

‘Dog.runs.down.street’ -Replace ( ‘.’ , ‘ ’)

# Results – ‘Dog runs down street

Type Operators

-is,-isnot Used to validate a .Net Type

(Get-Date) -is [DateTime] #Returns True

(Get-Date) -is [Int32] #Returns False

-as Converts input to .Net Type

‘4/1/2020’ -as [DateTime ]

#Returns Wednesday, April 1, 2020 12:00:00 AM

-f Format output of string objects

“{1} {0} {4}” -f ‘runs’ , ‘dog’ , ‘fast’ , ‘yellow’ , ‘slow’

# Result - ‘Dog runs slow’

New Operators

<Condition> ? <if-true> : <if-false> Ternary operator

$Path = ‘C:\Scripts’

(Test-Path $path) ? "Path exists" : "Path not found"

# Result is ‘Path exists’ if the c:\scripts path is present

|| , && Pipeline chain operators

#If process named ‘Chrome’ is found (left)/stop it (right)

Get-Process Chrome && Stop-Process -Name Chrome

# If the npm install fails, removenode_modules dir.

npm install || Remove-Item -Recurse ./node_modules

Null coalescing operators

$x = $null $x = $null

$x ?? 476 $x ??= 456

# Result 476 $x

# Result 476, $x is assigned this value

Assignment Operators

= Equal += Increments Value

-= Decrements value *= Multiplies value

/= Divides value %= Divide and assigns remainder

++ Increment value (+1) -- Decrement Value (-1)

BitWise Operators

** Only works with integers and works in binary form

-band Bitwise AND

-bor Bitwise OR (inclusive)

-bxor Bitwise OR (exclusive)

-bnot Bitwise NOT

-shl Bit shift left

-shr Bit shift right

** https://codesteps.com/2019/03/28/powershell-bitwise-logical-

operators/

[] Cast operator. Converts or limits object to type.

[DateTime]Today = ‘2/5/1999’

[Int32]$Counter = 59

, Comma operator, creates an array.

$ThisArray = 1, 2, 5

. Dot sourcing operator runs a script in the current

scope.

. C:\Scripts\QA\GetAll.ps1

| Pipeline operator. Sends output (‘pipes’) to

another cmdlet for processing.

Get-Mailbox | Set-Mailbox -RetentionPolicy ‘CorpReten’

.. Range Operator

20..33 # Lists numbers 20 through 33, incremented by 1's

Redirection Operators

>,>>,&> Sends the output of a stream to a file as well as

output of a particular type.

Output Streams * All Output

1 Success

2 Error

3 Warning

4 Verbose infor

5 Debug messages

6 Information

Redirection Operator examples:

# Writes warning output to warning.txt

Get-Mailbox 3> warning.txt

# Appends verbose.txt with the verbose output

Set-Computer 4>> verbose.txt

# Writes debug output to the output stream

Remove-AzVM 5>&1

# Redirects output to ADDCs.txt file

Get-ADDomainContrller > ADDCs.txt

Operators

https://devblogs.microsoft.com/powershell/announcing-PowerShell-7-0/

https://docs.microsoft.com/en-us/powershell/module/

microsoft.powershell.core/about/about_operators

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Automatic Variables

(not exhaustive)

Variables that store state information, created/maintained by

PowerShell and should be treated as Read-Only.

$$ Last token in the last line received by the

session

$? Contains the execution status of the last

command.

$^ Contains the first token in the last line received

by the session.

$_,$PSItem Current object in the pipeline object.

$args Contains an array of values for undeclared

parameters that are passed to a function, script,

or script block.

$ConsoleFileName Contains the path of the console file (.psc1)

that was most recently used in the session.

$Error Array of errors from previous commands.

$ExecutionContext Contains an EngineIntrinsics object that

represents the execution context of the

PowerShell host.

$foreach Contains the enumerator of a ForEach loop.

$HOME Full path of the user's home directory.

$Host Represents the current host application for

PowerShell.

$input Enumerates all input passed to a function.

$IsCoreCLR .NET Core Runtime check. $True/$False

$IsLinux $True if Operating system is Linux.

$IsMacOS $True if Operating system is Mac.

$IsWindows $True if Operating system is Windows.

$LastExitCode Exit code of the last Windows-based program

that was run.

$Matches Hash table of any string values matched with

the -match and -notmatch operators.

$MyInvocation Contains information about the current

command, such as the name, parameters,

parameter values, and more.

$null Represents an empty or null value.

$PID Process identifier (PID) of PowerShell session.

$PROFILE Full path of the PowerShell profile for the

current user and the current host application.

$PSCulture Reflects the culture of the current session.

$PSDebugContext This variable contains information about the

debugging environment.

$PSHome Full path of the installation directory for

PowerShell

$ConfirmPreference Determines whether PowerShell

automatically prompts you for

confirmation before running a

cmdlet or function.

$DebugPreference Determines how PowerShell

responds to debugging.

$ErrorActionPreference Determines how PowerShell

responds to a non-terminating error.

$ErrorView Determines the display format of

error messages in PowerShell.

$FormatEnumerationLimit Determines how many enumerated

items are included in a display.

$InformationPreference Lets you set information stream

preferences that you want displayed

to users.

$MaximumHistoryCount Determines how many commands

are saved in the command history

for the current session.

$OFS The Output Field Separator specifies

the character that separates the

elements of an array that is

converted to a string. Default (“ “)

$OutputEncoding Determines the character encoding

method that PowerShell uses when it

sends text to other applications.

$ProgressPreference Determines how PowerShell

responds to progress updates.

$PSEmailServer Specifies the default e-mail server

that is used to send email messages.

$PSSessionConfigurationName Specifies the default session

configuration that is used for

PSSessions created in the current

session.

$PSSessionOption Establishes the default values for

advanced user options in a remote

session.

$VerbosePreference Determines how PowerShell

responds to verbose messages

generated.

$WarningPreference Determines how PowerShell

responds to warning messages

generated.

$WhatIfPreference Determines whether WhatIf is

automatically enabled for every

command that supports it.

Preference Variables

$PSItem, $_. Contains the current object in the pipeline

object.

$PSScriptRoot Directory from which a script is being run.

$PSSenderInfo Contains the directory from which a script is

being run.

$PSUICulture Name of the user interface (UI) culture for OS.

$PSVersionTable Read-only hash table that displays details about

the version of PowerShell that is running in the

current session.

$PWD Path Object - full path of the current directory.

$ShellID Identifier of the current shell.

$StackTrace Stack trace for the most recent error.

$Switch Contains the enumerator not the resulting

values of a Switch statement.

https://docs.microsoft.com/en-us/powershell/module/

microsoft.powershell.core/about/about_automatic_variables

https://docs.microsoft.com/en-us/powershell/module/

microsoft.powershell.core/about/about_preference_variables

Variables

Examples: Change value of variable

$Path = ‘C:\Scripts\TestScript’ $Path = ‘C:\Windows\System32’

$Date = Get-Date $Date = ($Date).AddDays(-90)

$Processes = Get-Process $Processes = (Get-Process).Name

Clear Variable of values

Clear-Variable -Name $Path

Clear-Variable -Name $Date

Clear-Variable -Name $Processes

Scoped

$Global:Server=’Ex01' Global variable, visible everywhere

$Local:Count=1 Visible in local scope and child scopes

$Private:State=’Test’ Visible in local scope, but not child scopes

Multi-Assignment

$State,$Count,$PC = ‘Enabled’, ‘1', ‘Windows10’

Flip Variables

$Count1=3 ; $Count2=5 ; $Count1,$Count2 = $Count2,$Count1

Read-Only Variable (can be overwritten with -Force)

Set-Variable 'PermRef' -Value '1973' -Option ReadOnly

Constant Variable Cannot be overwritten

Set-Variable 'Important' -Value '1973' -Option Constant

Variable Acceptable Values:

[ValidateRange(90,150)][int]$Tolerance = 99

$Tolerance = 151 #Returns error – not valid for the variable

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'bob','r','smith' Array of strings

10,45,100 Array of integers

@() Empty array (initiate)

@(3) Array of 1 element

@(3,4,5) Array of 3 elements

2,(5,7),10 Array within an array

$Process[0] First element in an array

$Computer[2] Third element in an array

$User[5..14] Elements 6 through 15

$Server[-1] Returns last element

$Num[-4..-1] Returns last 4 elements

@(Get-AzVM) Stores results in an array

Reverse an Array

$a = 1,2,3,4,5

[array]::Reverse($a)

# $a would then store the values as 5,4,3,2,1

Combine Arrays (+)

$A = 1,2,3 ; $B = 4,5,6 ; $C = $A+$B

Create new array based on existing array

$SomePCs = $AllPCs[1,3,5,7+9..13]

Starting a line with a ‘#’ makes the line a comment

# Load PowerShell Modules

$Var = ‘#Not a comment example’

# Write-Host ‘But this is an example’

$State = ‘Enabled’ # Set the State variable

Multi-Line Comments

Synopsis: This is a section of comments.

Purpose: To enclose a large section of text. Possibly to be

used as a header for a script.

Version: 1.0

Parameters: None

‘String – this is an example’

“Contains a $Variable that displays its value”

‘Single quotes $Variable whose content is not displayed’

@”

This is a more versatile string that can store quotes, returns

and can also evaluate variables. For example. Today’s date:

$Date

Then we can close it off like we started this string.

“@

@’

This one is less versatile as it will not evaluate variables:

$Date

Then we can close it off like we started this string.

‘@

Helpful Tips

Use tab to autocomplete cmdlets

Tab through parameters to see all available

Check for latest module versions

Read latest Microsoft Docs for PowerShell

Read PowerShell MVP blogs for more tips

Remove line wrapping from PowerShell session

TAB Autocomplete or cycle through all options

Ctrl+Space Display all available parameters/switches

Ctrl+V Copy data to session

Properties for an object can be accessed with ‘.’ followed by

the property name. For example:

$Process = Get-Process 'Chrome'

$Process.ID

$DC = get-adcomputer dc01 -Properties *

$DC.dSCorePropagationData

If there are sub-properties, add with the ‘.’ separator:

$DC.dSCorePropagationData.Date

For Static Properties use ::

[datetime]::Now

Object Properties

StringsCommentsArrays

$Hash = @ { } Creates an empty hash table

$Hash =@{ColorOne = ‘Red’} Creates hash table with data

$Hash.ColorOne Display ColorOne key

$Hash.ColorTwo = ‘Green’ Assigns ‘Green’ to this key

Add values to hash

$Color = ‘ColorThree’ ; $Value = ‘White’

$Hash.Add($Color,$Value)

Remove value from hash

$Hash.Remove(‘ColorTwo’)

Sort table by Key values

$Hash =@{ColorOne = 'Red'}

$Hash.ColorTwo = 'Green'

$Color = 'ColorThree' ; $Value = 'Blue'

$Hash.Add($Color,$Value)

$Hash.Remove('ColorTwo')

$Hash.GetEnumerator() | Sort-Object -Property Value

Hash Tables

https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_hash_tables

Foreach

The Foreach statement steps (iterates) through a series of values in

a collection of items.

$CSVFileData = Import-CSV “C:\Data.csv”

Foreach ($Line in $CSVFileData) {

$DisplayName = $Line.DisplayName

$Size = $Line.MailboxSizeMB

Write-host “$DisplayName mailbox = $Size MB .”

}

ForEach-Object (Parallel – New Feature)

$Logs | Foreach-Object -Parallel {$File = $_+'.txt';get-winevent -

LogName $_ -MaxEvents 5000 > $File } -ThrottleLimit 10

Do While

Traverses list one or more times, subject to a While condition.

$Counter = 1

Do {

Write-Host “This is pass # $counter for this loop.”

$Counter++

} While ($Counter -ne 1000)

Do Until

Traverses list one or more times, subject to a Until condition.

$Users = Get-ADUser

Do {

Foreach ($User in $Users) {

$State = $Users.Enabled

$FirstDisabledUserAccount = $User

}

} Until ($State -eq ‘Disabled)

Loops

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PowerShell 7.0 - Quick Reference

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New to PowerShell 7.0 is the concept of Experimental Features. These features are testing newly

developed modules, in test and not production.

List any Experimental Features available to PowerShell 7.0's shell:

Get-ExperimentalFeature

Disable an Experimental Feature (if further development is needed, for example):

Disable-ExperimentalFeature

Enable a new experimental feature or to enable an existing disabled feature (Microsoft’s examples):

Enable-ExperimentalFeature

Experimental Features

Reference: https://github.com/powershell/powershell#get-powershell

Windows Server 2008 R2, 2012, 2012 R2, 2016, and 2019

Windows 7, 8.1, and 10 macOS 10.13+

Red Hat Enterprise Linux (RHEL) / CentOS 7+ Fedora 29+

Debian 9+ Ubuntu 16.04+

openSUSE 15+ Alpine Linux 3.8+

ARM32 and ARM64 flavors of Debian and Ubuntu ARM64 Alpine Linux.

Compatibility

New cmdlet – Get-Error

Use this cmdlet to retrieve past error messages.

Examples

Get-Error # Diplays the last error message

Get-Error -Newest 2 # Displays last two error messages

Pause and Sleep

Add a pause or have PowerShell ‘Sleep’ for a matter of seconds

Pause # waits for operator to hit the ‘Enter’ key

Sleep 10 # Waits 10 seconds and then moves on

Write-Host

Can be used to display variable content, known possible errors

Write-Host ‘Step 1’

Write-Host ‘Step 2’

Write-Host ‘Step 3’

Write a Windows Event

New-winevent -ProviderName Microsoft-Windows-PowerShell

-ID 8196

Get-WinEvent -ProviderName Microsoft-Windows-PowerShell

-MaxEvents 100

List Providers

Get-NetEventProvider -ShowInstalled | Ft Name

Comments

Use comments to remove a one-liner or cmdlet from executing

# Set-Mailbox -RetentionPolicies Temp

Try and Catch

Used to catch errors and perform secondary/final actions.

Try {

Set-ADForestMode -Identity corp.loc -ForestMode

Windows2016Forest

} Catch {

Write-Host ‘AD cmdlet failed to execute.’ -ForegroundColor Red

}

Supported Modules

* All modules supported by PowerShell 6

Incompatible modules

Import-Module -UseWindowsPowerShell <Module Name>

# Uses local WindowsPowerShell for this module

List all executed commands for the current session:

Get-History List all previous commands

Get-History -Id 17 | Fl List the 17

executed command

Clear-History Remove all entries from the history

Add-History Add additional entries to the history

Invoke-History -Id 12 Re-runs item 12 from the history

https://docs.microsoft.com/en-us/powershell/module/

microsoft.powershell.core/about/about_history?view=powershell-7

Dates can be important in PowerShell

Get-Date Displays the current date and time

(Get-Date).AddDays(-30) Displays the date from 30 days ago

(Get-Date).AddHours(4) Displays the time 4 hours from now

Format date examples:

Get-Date -Format yyyymmdd-hhmmss

Get-Date -Format "MM.dd.yyyy-hh.mm-tt"

List items in a graphic format

$Processes | Out-GridView Displays running process in a grid

List items in a grid, allows selection and pass back to session

$Processes | Out-GridView -PassThru

Measure how long a function takes to execute:

$StopWatch = [Diagnostics.Stopwatch]::StartNew()

& $FunctionToExecute

$StopWatch.Stop()

$StopWatch.Elapsed

Measure-Command {$FunctionToExecute}

File Output

Get-AzVM | Export-CSV AzureVirtualMachines.csv

Get-AdComputer -Filter * | Out-File AllDomainComputers.txt

Get-Process | Out-File AllProcesses.txt -Append -NoClobber

Working with Modules

PowerShell cmdlets are grouped my modules. We can work with

supported cmdlets from any module. We can also load and

unload modules as needed depending on if we need more cmdlets.

List Modules

Get-Module Lists loaded modules

Get-Module -ListAvailable Lists all available modules

Load and unload modules

Import-Module ActiveDirectory Loads ActiveDirectory module

Remove-Module AZ Unloads the AZ module

List cmdlets for a module

$Module = ‘SharePointPnPPowerShellOnline’

Import-Module $Module

Get-Command |Where {$_.Source -eq 'SharePointPnPPowerShellOnline'}

Locate a Module in a repository

Find-module MicrosoftTeams

Find-module ExchangeOnline* #Can use wildcards

Install Module

Install-Module MicrosoftTeams

Find-module ExchangeOnlineManagement

Other Module functions

Uninstall-Module LyncOnlineConnector

Update-Module ExchangeOnlineManagement