PowerShell: Regular Expression Operators

String Match by Regex

-match

String matches regex pattern. Case-insensitive.

match result stored in $Matches

# check if contain 3 digits
# the regex must be on right side
"some_724.jpg" -match "\d{3}"
# True

-iMatch

Case-insensitive. Same as -Match.

-cMatch

Case-sensitive

-notMatch

Negation.

-iNotMatch

Case-insensitive. Same as -Notmatch.

-cNotMatch

Case-sensitive

String Regex Replace

-Replace

Replace the matched part of a regex in string. Case-Insensitive.

match result stored in $Matches

# replace the regex match part of a string
$output = "some 04/02/2025 yes" -replace "(\d{2})/(\d{2})/(\d{4})", '$3-$1-$2'
Write-Host $output
# some 2025-04-02 yes

-iReplace

Case-insensitive. Same as -Replace.

-cReplace

Case-sensitive

Escape Regex Meta Characters

[Regex]::Escape()

escape regex meta characters. Useful when a command or operator that takes regex, but you need plain text search.