Regular Expressions 101

Community Patterns

22

Get path from any text

Created·2023-01-31 14:38
Updated·2023-07-23 20:17
Flavor·PCRE2 (PHP)
Recommended·
Get path (windows style) from any type of text (error message, e-mail corps ...), quoted or not. THIS IS THE SINGLE LINE VERSION ! If you want understand how it work or edit it, go https://regex101.com/r/7o2fyy Relative path are not supported The goal is to catch what "Look like" a path. See the limitations UNC path and prefix path like //./], [//?/] or [//./UNC/] are allowed some url path like [file:///C:/] or [file://] are allowed Catch path quoted with ["] and [']. But these quotes are include with the catch Quoted path is not concerned by limitations Limitations : (only unquoted path) [dot] and [space] is allowed, but not in a row [dot+space] or [space+dot at end of file name isn't catched INSIDE A NAME FILE (or last directory if it is a path to a directory) : [comma] is not supported (it stop the catch) after a first [dot], any [space] stop the catch after a [space], catch is stoped if next character is not a [letter], [digit] or [-] so, double [space] stop the catch Compatibility compatible PCRE, PCRE2 AutoHotkey : don't forget to escape "%" in "`%" /!\ Powershell and .Net /!\\ : this regex need some modification to be interpreted by powershell. You have to replace each (?&CapturGroupName) by \k. Use this powershell code to do this replacement : ` $powershellRegex = @' [Put here the regex to replace (?&CapturGroupName) with \k] '@ -replace '\(\?&(\w+)\)', '\k' ` This example code must return : [Put here the regex to replace \k with \k]
Submitted by nitrateag

Community Library Entry

1

Regular Expression
Created·2025-11-04 19:49
Flavor·PCRE2 (PHP)

/
^((?!\.)(?!.*\.\.)[\w!#$%&'*+\/=?^`{|}~.-]+(?<!\.))@([a-zA-Z0-9](?:[a-zA-Z0-9_-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9_-]{0,61}[a-zA-Z0-9])?)+)$
/
gm
Open regex in editor

Description

Core principles Covers ~99% of practical use cases Returns exactly 2 capturing groups (username and domain) Balances between RFC 5322 compliance and practicality

Accepts: Basic email addresses Special characters: `! # $ % & ' * + / = ? ^ \ { | } ~ `` Dots, hyphens, underscores in username Hyphens and underscores in domain Multi-level domains (e.g., .co.uk) Username starting with _ or - Username ending with special characters (e.g., +)

Rejects: Username starting/ending with a dot Double dots in username or domain Missing TLD Domain starting/ending with a hyphen Spaces, quotes, parentheses Multiple @ signs IP addresses in square brackets

Submitted by gh/barabasz