1
2
3
Get-Process  # List running processes
Stop-Service # Stop a Windows service

1
2
3
4
5
Get-Process | Where-Object { $_.CPU -gt 10 } | Sort-Object CPU

# Parallel pipeline processing (PowerShell 7+)
1..10 | ForEach-Object -Parallel { "Processing $_"; Start-Sleep 1 } -ThrottleLimit 5

1
2
3
4
5
6
# Run next command only if previous succeeded
Test-Path file.txt && Get-Content file.txt

# Run next command only if previous failed
Test-Path file.txt || New-Item file.txt

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
# Get help for a specific cmdlet
Get-Help Get-Process

# Get detailed help with examples
Get-Help Get-Process -Detailed
Get-Help Get-Process -Examples
Get-Help Get-Process -Online   # Open online docs in browser

# Update local help content (run elevated)
Update-Help

# List all commands
Get-Command

# Find commands by verb or noun
Get-Command -Verb Get
Get-Command -Noun Process

# Discover object properties and methods
Get-Process | Get-Member

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
# Basic variables
$name = "John Doe"
$age = 30
$isActive = $true

# Arrays
$fruits = @("Apple", "Banana", "Cherry")

# Hashtables (Dictionaries)
$person = @{
    Name = "John"
    Age = 30
    City = "New York"
}

# Ordered hashtable (preserves insertion order)
$ordered = [ordered]@{ First = 1; Second = 2; Third = 3 }

# Type casting
[int]$number = "42"
[string]$text = 123

# Null-coalescing and null-conditional (PowerShell 7+)
$value = $null ?? "default"          # Returns "default"
$user?.Address?.City                  # Safe member access
$cache ??= (Get-ExpensiveData)        # Assign if null

1
2
3
4
5
6
7
8
$a = 10
$b = 3
$sum = $a + $b        # Addition
$diff = $a - $b       # Subtraction
$prod = $a * $b       # Multiplication
$div = $a / $b        # Division
$mod = $a % $b        # Modulus

1
2
3
4
5
6
7
8
9
10
-eq    # Equal
-ne    # Not equal
-gt    # Greater than
-ge    # Greater than or equal
-lt    # Less than
-le    # Less than or equal

# Example
if ($a -gt $b) { "A is greater than B" }

1
2
3
4
5
6
7
8
9
10
11
-and   # Logical AND
-or    # Logical OR
-not   # Logical NOT
-xor   # Logical XOR

# Example
if (($x -gt 10) -and ($x -lt 20)) { "x is between 10 and 20" }

# Ternary operator (PowerShell 7+)
$status = ($age -ge 18) ? "Adult" : "Minor"

1
2
3
4
5
6
7
8
if ($condition) {
    # Code if true
} elseif ($another_condition) {
    # Alternative condition
} else {
    # Default action
}

1
2
3
4
5
6
7
8
9
10
11
12
switch ($value) {
    1 { "One" }
    2 { "Two" }
    default { "Other" }
}

# Switch with regex and wildcard
switch -Regex ($input) {
    '^\d+$'   { "Number" }
    '^[a-z]+' { "Lowercase word" }
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
# For Loop
for ($i = 0; $i -lt 10; $i++) {
    Write-Host $i
}

# Foreach Loop
$fruits = @("Apple", "Banana", "Cherry")
foreach ($fruit in $fruits) {
    Write-Host $fruit
}

# While Loop
$count = 0
while ($count -lt 5) {
    Write-Host $count
    $count++
}

# Do-While / Do-Until
do { $n = Read-Host "Enter Q to quit" } until ($n -eq 'Q')

1
2
3
4
5
6
7
function Greet {
    param($name)
    return "Hello, $name!"
}

Greet -name "John"

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
function Process-Items {
    [CmdletBinding()]
    param(
        [Parameter(ValueFromPipeline=$true)]
        [ValidateNotNullOrEmpty()]
        $InputObject
    )
    begin   { # one-time setup }
    process {
        # Process each pipeline item
        $InputObject | ForEach-Object {
            # Do something with $_
        }
    }
    end     { # one-time cleanup }
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
# List files and folders
Get-ChildItem C:\

# Copy item
Copy-Item source.txt destination.txt

# Move item
Move-Item old_location new_location

# Remove item
Remove-Item file.txt

# Create directory
New-Item -ItemType Directory -Path "C:\NewFolder"

# Compress / expand archives
Compress-Archive -Path C:\Logs\*.log -DestinationPath C:\logs.zip
Expand-Archive  -Path C:\logs.zip -DestinationPath C:\Extracted

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
$text = "Hello, World!"
$text.ToUpper()        # Uppercase
$text.ToLower()        # Lowercase
$text.Contains("World") # Check substring
$text.Replace("World", "PowerShell")

# Split and Join
$words = "one two three".Split()
$joined = $words -join ","

# Here-strings for multi-line text
$multi = @"
Line 1
Line 2
"@

1
2
3
4
5
6
7
$process = Get-Process chrome
$process.Name        # Access object property
$process | Select-Object Name, CPU, Id  # Select specific properties

# Build custom objects
[pscustomobject]@{ Name = "John"; Age = 30 }

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
# Filter processes
Get-Process | Where-Object { $_.CPU -gt 10 }

# Simplified Where syntax (PowerShell 3+)
Get-Process | Where-Object CPU -gt 10

# Select top 5 processes by CPU
Get-Process | Sort-Object CPU -Descending | Select-Object -First 5

# Group objects
Get-Process | Group-Object Company

# Parallel filtering (PowerShell 7+)
$servers | ForEach-Object -Parallel { Test-Connection $_ -Count 1 -Quiet } -ThrottleLimit 10

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
try {
    # Risky operation
    $result = Invoke-WebRequest -Uri "https://example.com"
} catch [System.Net.WebException] {
    Write-Host "Web error: $($_.Exception.Message)"
} catch {
    Write-Host "An error occurred: $_"
} finally {
    # Cleanup code
}

# Suppress errors
Get-ChildItem -ErrorAction SilentlyContinue

# Get the last error
$Error[0] | Format-List -Force

# Pretty error view (PowerShell 7+)
$ErrorView = 'ConciseView'   # or 'NormalView', 'CategoryView', 'DetailedView'
Get-Error                     # Detailed inspection of last error

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
# Connect to remote computer (WinRM)
Enter-PSSession -ComputerName RemoteServer

# Run command on remote computer
Invoke-Command -ComputerName RemoteServer -ScriptBlock {
    Get-Process
}

# SSH-based remoting (cross-platform, PowerShell 7+)
Enter-PSSession -HostName user@linuxhost -SSHTransport
Invoke-Command -HostName server01,server02 -SSHTransport -ScriptBlock { uptime }

# Persistent sessions
$s = New-PSSession -ComputerName RemoteServer
Invoke-Command -Session $s -ScriptBlock { Get-Service }
Remove-PSSession $s

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
# List installed modules
Get-Module -ListAvailable

# Import a module
Import-Module ActiveDirectory

# Install a module from the PowerShell Gallery
Install-Module PSReadLine -Scope CurrentUser

# Find modules
Find-Module -Name *Azure*

# Update modules
Update-Module PSReadLine

# Microsoft.PowerShell.PSResourceGet (modern replacement for PowerShellGet, ships with PS 7.4+)
Install-PSResource Microsoft.Graph
Find-PSResource    Az
Update-PSResource  PSReadLine

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
# List services
Get-Service

# Start/Stop service
Start-Service -Name "wuauserv"
Stop-Service -Name "wuauserv"

# List processes
Get-Process

# Stop a process
Stop-Process -Name notepad

# Note: Get-EventLog is deprecated; use Get-WinEvent (see section 16)

1
2
3
4
5
6
7
8
9
10
# Read registry key
Get-ItemProperty "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion"

# Set registry value
Set-ItemProperty -Path "HKCU:\Path\To\Key" -Name "ValueName" -Value "NewValue"

# Create a new key / value
New-Item        -Path "HKCU:\Software\MyApp" -Force
New-ItemProperty -Path "HKCU:\Software\MyApp" -Name "Version" -Value "1.0" -PropertyType String

1
2
3
4
5
6
# Modern, cross-architecture cmdlet (preferred)
Get-WinEvent -LogName System -MaxEvents 10
Get-WinEvent -FilterHashtable @{ LogName='Application'; Level=2; StartTime=(Get-Date).AddHours(-1) }

# Legacy cmdlets (Get-EventLog / Clear-EventLog) are deprecated and unavailable in PowerShell 7+

1
2
3
4
5
# Requires the ActiveDirectory module (RSAT)
Get-ADUser -Filter *
Get-ADUser -Identity jdoe -Properties MemberOf
New-ADUser -Name "John Doe" -SamAccountName jdoe -AccountPassword (Read-Host -AsSecureString) -Enabled $true

1
2
3
4
5
6
7
8
9
10
11
12
13
14
# CSV
Import-Csv file.csv
Get-Process | Export-Csv output.csv -NoTypeInformation

# JSON
ConvertTo-Json   @{ name="John"; age=30 } -Depth 5
ConvertFrom-Json '{"name":"John","age":30}'

# JSON with comments / trailing commas (PowerShell 7+)
'{ "x": 1, /* comment */ }' | ConvertFrom-Json -AsHashtable

# XML
[xml]$xml = Get-Content file.xml

1
2
3
4
5
6
7
# Create scheduled task (Windows)
$action  = New-ScheduledTaskAction  -Execute "notepad.exe"
$trigger = New-ScheduledTaskTrigger -Daily -At 9am
Register-ScheduledTask -TaskName "DailyNotepad" -Action $action -Trigger $trigger

# On Linux/macOS use cron, systemd timers, or launchd with pwsh

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
# Check current execution policy
Get-ExecutionPolicy -List

# Set execution policy
Set-ExecutionPolicy RemoteSigned -Scope CurrentUser

# Run unsigned script (one-off)
pwsh -ExecutionPolicy Bypass -File script.ps1

# Secret management (Microsoft.PowerShell.SecretManagement)
Install-Module Microsoft.PowerShell.SecretManagement, Microsoft.PowerShell.SecretStore
Register-SecretVault -Name LocalStore -ModuleName Microsoft.PowerShell.SecretStore -DefaultVault
Set-Secret -Name ApiKey -Secret "supersecret"
Get-Secret -Name ApiKey -AsPlainText

1
2
3
4
5
6
7
8
9
10
11
# Disk management
Get-Disk
Get-Partition
Get-Volume

# Network troubleshooting
Test-Connection google.com -Count 2
Test-NetConnection google.com -Port 443
Get-NetIPConfiguration
Resolve-DnsName example.com

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
# Verbose / debug output
$VerbosePreference = 'Continue'
$DebugPreference   = 'Continue'

# Step-debug a script
Set-PSBreakpoint -Script .\myscript.ps1 -Line 10
Set-PSBreakpoint -Command Get-Process

# Trace script execution
Set-PSDebug -Trace 1

# Capture a session transcript
Start-Transcript -Path .\session.log
Stop-Transcript

# Inspect the most recent error in detail (PowerShell 7+)
Get-Error

1
2
3
4
5
6
7
8
9
10
11
12
13
# Detect host OS (automatic variables available in PowerShell 6+)
if ($IsWindows) { "Windows" }
elseif ($IsLinux)   { "Linux" }
elseif ($IsMacOS)   { "macOS" }

# Modern web requests (HTTP/2 supported on PS 7.2+)
Invoke-RestMethod -Uri 'https://api.github.com/repos/PowerShell/PowerShell' -Method Get
Invoke-WebRequest -Uri 'https://example.com' -OutFile page.html

# JSON Web Token style auth header
$headers = @{ Authorization = "Bearer $token" }
Invoke-RestMethod -Uri $url -Headers $headers