Exploring Match-Object in PowerShell

The Core Concept: Text vs. Objects

• Linux/Bash: You pipe Text. Tools like grep, awk, and sed manipulate strings.
• PowerShell: You pipe Objects (structured data). It is conceptually closer to jq (processing JSON) than it is to awk.

1. The grep Equivalents

If you are searching inside files or raw text output.

PowerShell: Select-String (Best)

Standard regex support (.NET), case-insensitive by default.

• Alias: sls (or grep in generic setups).
• Syntax:

  # Search all text files recursively
  Get-ChildItem -Recurse *.txt | Select-String "my_pattern"
  
  # Search with Regex
  Select-String "\d{}-\d{2}" access.log

CMD: findstr (Legacy)

Limited regex, legacy tool.

• Syntax: findstr /s /i "my_string" *

2. Filtering Command Output (The “jq” Way)

Since PowerShell commands output Objects, piping to Select-String often fails (or returns nothing) because the string representation of an object doesn’t always contain the text displayed on the screen.

Use Where-Object (Alias ?) to filter by property.

• The Syntax: $_ represents the current object in the pipeline (like jq or awk’s $0).

• Example:

  # Filter Services (Object approach - Recommended)
  Get-Service | Where-Object { $_.Status -eq "Running" }
  
  # Filter Processes using Regex
  Get-Process | Where-Object { $_.Name -match "^sv" }

• The “Visual” Workaround: If you absolutely just want to “grep the screen” exactly as it looks, convert the objects to text streams first:

  Get-Service | Out-String -Stream | Select-String "Running"

3. The find Equivalent (File Search)

Use Get-ChildItem (Alias ls, dir, gci).

• Find by Name:

  # Linux: find . -name "*.txt"
  Get-ChildItem -Filter "*.txt" -Recurse

• Find by Size/Date (Using Object Logic):

  # Linux: find . -size +100M
  Get-ChildItem -Recurse | Where-Object { $_.Length -gt 100MB }

• Pathing: You can pass paths directly: ls C:\Windows, C:\Users.

4. Cheat Sheet: Linux vs. PowerShell Operators

PowerShell operators use dashes because > and < are reserved for file redirection. They are case-insensitive by default.

Linux/Logic	PowerShell Operator	Case-Sensitive Version
==	-eq	-ceq
!=	-ne	-cne
> / <	-gt / -lt	-cgt / -clt
grep (Regex)	-match	-cmatch
Wildcard (*)	-like	-clike
&& (Logical)	-and	N/A
`		` (Logical)