Powershell-Training/6.File_Management/File Management with PowerShell.md

File Management with PowerShell

Get-ChildItem

Get the content of a curent directory Alias = ls

Get-ChildItem

Get-ChildItem C:\Windows

Set-Location

Change current directory Alias = cd

Set-Location

ACL

Windows Access Control Lists (ACLs) are a core security mechanism used to control access to files, folders, and other system objects. An ACL defines which users or groups are allowed or denied specific permissions, such as read, write, modify, or execute. Each ACL is made up of Access Control Entries (ACEs) that explicitly grant or restrict these permissions. By using ACLs, Windows ensures that only authorized users can access or modify resources, helping to protect system integrity and sensitive data.

Get-Acl

for listing permision for a file

Get-ACL "C:\mrsh\test.ps1"

$file = Get-ACL 

$file.Access

Get-ACL "C:\mrsh\test.ps1" | Format-List

Set-ACL

$acl = Get-Acl "C:\mrsh\test.ps1"
$permission = "Administrator", "FullControl", "Allow"
$accessRule = New=Object System.Security.AccessControl.FileSystemAccessRule $permission
$acl.SetAccessRule($accessRule)

Set-ACL "C:\mrsh\test.ps1" $acl

File size

$fileSize = Get-ChildItem -Path "C:\mrsh\test.ps1" -Recurse -Force | Measure-Object -Property Length -Sum

$fileSize.Sum/1KB

Environement Variable

Environment variables in PowerShell are used to store system-wide or user-specific values that programs and scripts can access during execution. They help manage configuration settings such as file paths, system behavior, or application options without hard-coding them into scripts. In PowerShell, environment variables are accessed through the Env: drive, for example $Env:PATH, and can be created or modified using simple assignment. This makes scripts more flexible, portable, and easier to maintain across different systems.

$env:ProgramFiles
$env:ProgramData
$env:SystemDrive
$env:SystemRoot

Match Replace

$string = "Jello world!"

if($string -match "Hello"){
    Write-Output "The string matches the pattern!"
    $newString = $string -replace "Hello" , "Hi"
    Write-Output $newString
}

TextFile

Text files are commonly used to store and exchange data in a simple, readable format.

Set-Content

The Set-Content cmdlet is used to create a new text file or overwrite an existing one with specified content.

Set-Content -Path "C:\mrsh\endor.txt" -Value "Ewoks"

Get-Content

The Get-Content cmdlet is used to read the contents of a text file, returning its data line by line, which is useful for processing or analyzing text.

Get-Content -Path "./endor.txt"

Add-Content

Add-Content -Path "C:\mrsh\endor.txt" -Value "Jedi"

CSV

In PowerShell, CSV (Comma-Separated Values) files are widely used for storing and exchanging structured data such as tables and lists.

Import-CSV

PowerShell provides the Import-Csv cmdlet to read CSV files and convert each row into an object with properties based on the column headers, making the data easy to work with.

Import-CSV -Path ".\Simpsons.csv"

Export-CSV

The Export-Csv cmdlet is used to save objects back into a CSV file. This object-based approach allows for efficient data manipulation, filtering, and reporting.

Get-ComputerInfo | Export-CSV -Path "C:\mrsh.com\same-simpson.csv" 

JSON

In PowerShell, JSON (JavaScript Object Notation) is commonly used to store and exchange structured data in a lightweight, human-readable format. This makes it easy to work with APIs, configuration files, and complex data structures. JSON support in PowerShell enables seamless data interchange and efficient automation.

ConvertFrom-Json

The ConvertFrom-Json cmdlet to transform JSON data into PowerShell objects.

$json = Get-Content -Path ".\simpsons.json" -Raw
$data = ConvertFrom-Json -InputObject $json

ConvertTo-Json

and ConvertTo-Json to convert objects back into JSON format.

Get-NetAdapter | ConvertTo-Json | Out-File ".\NetworkAdapter.json"

XML

In PowerShell, XML is used to store and manage structured data in a hierarchical format. XML data is represented as objects, making it easy to navigate, extract, and modify elements and attributes. This makes XML useful for working with configuration files, system data, and applications that rely on structured document formats.

$xml_file = Get-Content C:\mrsh\simpsons.xml
$xml_file.simpsons.charcter[0]
$xml_file.save("C:\mrsh\simpsons-nex.xml")