PowerShell Cmdlets Overview - MSDN Documentation

What are PowerShell Cmdlets?

PowerShell cmdlets (pronounced "command-lets") are lightweight, native .NET classes designed to perform specific actions in the PowerShell environment. They are the fundamental commands used for automation and configuration management in Windows.

Unlike traditional command-line executables (.exe files), cmdlets are designed to return objects, not just text. This object-oriented approach allows for more powerful and flexible manipulation of data.

Cmdlet Naming Convention

Cmdlets follow a consistent naming convention: Verb-Noun. This pattern makes it easier to understand the action a cmdlet performs and the object it operates on.

Verb: Describes the action (e.g., Get, Set, New, Remove, Stop, Start).
Noun: Describes the object the action is performed on (e.g., Process, Service, Computer, File).

For example:

Get-Process: Retrieves a list of running processes.
Set-Service: Modifies the properties of a service.
New-Item: Creates a new item, such as a file or directory.
Remove-Item: Deletes an item.

Common Cmdlet Parameters

Cmdlets can accept parameters to modify their behavior. Some parameters are common to many cmdlets:

-Verbose: Displays detailed information about the operation.
-Debug: Displays debugging information.
-ErrorAction: Specifies how PowerShell responds to a non-terminating error (e.g., SilentlyContinue, Stop, Continue).
-WhatIf: Shows what would happen if the command were run, without actually making any changes.
-Confirm: Prompts for confirmation before executing the command.

Discovering Cmdlets

You can discover available cmdlets using the Get-Command cmdlet:

Example: Find all cmdlets related to services

Get-Command -Noun Service

To get help on a specific cmdlet, use the Get-Help cmdlet:

Example: Get help for Get-Process

Get-Help Get-Process

You can also specify parameter-specific help:

Get-Help Get-Process -Parameter Name

Key Cmdlets for System Management

Process Management

Example: List all running processes

Get-Process

Example: Stop a specific process by name

Stop-Process -Name "notepad"

Service Management

Example: List all services

Get-Service

Example: Start a service

Start-Service -Name "Spooler"

Example: Restart a service

Restart-Service -Name "Spooler"

File and Directory Management

Example: List files and directories in the current location

Get-ChildItem

Example: Create a new directory

New-Item -Path "C:\Temp\MyNewFolder" -ItemType Directory

Example: Copy a file

Copy-Item -Path "C:\Source\MyFile.txt" -Destination "C:\Destination\"

Conclusion

Understanding PowerShell cmdlets is crucial for efficient system administration and automation. Their consistent naming, object-oriented nature, and extensive parameter support make them a powerful tool for managing Windows environments.