Working with Files & Folders 📁

# A "provider" exposes some data store as if it were a disk drive.
# Get-PSProvider lists them; Get-PSDrive lists the drives they expose.
Get-PSProvider | Select-Object Name, Drives

# Because the FileSystem and Registry are BOTH providers, the SAME
# commands work on each — you just point them at a different drive.
Set-Location C:\           # move into the C: file-system drive
Set-Location HKCU:\        # move into the registry "current user" drive (Windows)

Name         Drives
----         ------
Registry     {HKLM, HKCU}
Alias        {Alias}
Environment  {Env}
FileSystem   {C, D, Temp}
Function     {Function}
Variable     {Variable}
Certificate  {Cert}

# Get-ChildItem lists what's inside a folder. Aliases: gci, ls, dir.
Get-ChildItem -Path C:\Projects

# Set-Location changes the current folder. Aliases: cd, sl.
Set-Location C:\Projects\my-app
Get-Location                       # where am I now?  (alias: pwd)

# -Recurse digs into sub-folders; -Filter narrows by name pattern.
Get-ChildItem -Path C:\Projects -Recurse -Filter "*.log"

    Directory: C:\Projects

Mode    LastWriteTime        Length Name
----    -------------        ------ ----
d----   2026-06-10  09:14           my-app
d----   2026-06-11  16:02           archive
-a---   2026-06-12  08:30      482  notes.txt

Path
----
C:\Projects\my-app

    Directory: C:\Projects\my-app\logs

Mode    LastWriteTime        Length Name
----    -------------        ------ ----
-a---   2026-06-12  08:30      120  app.log

# New-Item makes files OR folders — choose with -ItemType.
New-Item -ItemType Directory -Path ".\reports"            # a new folder
New-Item -ItemType File -Path ".\reports\june.txt"       # an empty file

# Copy-Item duplicates; Move-Item moves OR renames (no separate Rename needed).
Copy-Item ".\reports\june.txt" ".\reports\june-backup.txt"
Move-Item ".\reports\june.txt" ".\reports\2026-june.txt"   # this is a rename

# Test-Path returns a plain True/False — perfect for an "if".
Test-Path ".\reports\2026-june.txt"

    Directory: C:\Projects\my-app

Mode    LastWriteTime        Length Name
----    -------------        ------ ----
d----   2026-06-15  10:01           reports

    Directory: C:\Projects\my-app\reports

Mode    LastWriteTime        Length Name
----    -------------        ------ ----
-a---   2026-06-15  10:01        0  june.txt

True

# 🎯 YOUR TURN — replace each ___ then run it in PowerShell.

# 1) Create a folder called "notes" in the current directory
New-Item -ItemType ___ -Path ".\notes"          # 👉 Directory or File?

# 2) Write a first line into notes\todo.txt (this also CREATES the file)
Set-Content -Path ".\notes\todo.txt" -Value ___    # 👉 some "text in quotes"

# 3) Append a second line to the same file
___ -Path ".\notes\todo.txt" -Value "Walk the dog"  # 👉 which cmdlet APPENDS?

# Already wired up — reads the file back once your lines work:
Get-Content ".\notes\todo.txt"

# ✅ Expected output (if line 2 was "Buy milk"):
#    Buy milk
#    Walk the dog

Buy milk
Walk the dog

# Set-Content WRITES (and overwrites) the whole file.
Set-Content -Path ".\reports\log.txt" -Value "Service started"

# Add-Content APPENDS a new line to the end.
Add-Content -Path ".\reports\log.txt" -Value "Request handled"
Add-Content -Path ".\reports\log.txt" -Value "Service stopped"

# Get-Content READS the file. It returns an ARRAY: one item per line.
Get-Content -Path ".\reports\log.txt"

# So .Count is the number of lines, and [0] is the first line.
(Get-Content ".\reports\log.txt").Count     # 3
(Get-Content ".\reports\log.txt")[0]        # the first line

Service started
Request handled
Service stopped
3
Service started

# Remove-Item deletes. On a FOLDER you must add -Recurse to remove
# its contents too, otherwise PowerShell prompts you for confirmation.

# ALWAYS preview first with -WhatIf — it shows what WOULD happen,
# but changes nothing on disk.
Remove-Item ".\reports" -Recurse -WhatIf

# Happy with the preview? Run the real thing (drop -WhatIf).
Remove-Item ".\reports" -Recurse

What if: Performing the operation "Remove Directory" on target "C:\Projects\my-app\reports".
What if: Performing the operation "Remove File" on target "C:\Projects\my-app\reports\log.txt".

# 🎯 YOUR TURN — only delete the folder if it actually exists.

$folder = ".\notes"

# 1) Check whether the folder exists (returns True / False)
if (___ $folder) {                  # 👉 which cmdlet checks a path exists?

    # 2) Preview the delete safely first — add the right switch
    Remove-Item $folder -Recurse ___    # 👉 the "preview, change nothing" switch

    Write-Output "Previewed delete of $folder"
} else {
    Write-Output "Nothing to delete"
}

# ✅ Expected output (when .\notes exists):
#    What if: Performing the operation "Remove Directory" on target "...\notes".
#    Previewed delete of .\notes

What if: Performing the operation "Remove Directory" on target "C:\Projects\my-app\notes".
Previewed delete of .\notes