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

0

Regular Expression
Created·2022-03-31 14:24
Flavor·PCRE2 (PHP)

/
^([-\w\d\.]+?)(?(?=_)|(?=\.jpg))
/
gm
Open regex in editor

Description

For a batch of photos named in the following fashion: {SKU}_{#}.jpg, where the _{#} is optional, only present when the photo is part of an image gallery for a given SKU.

This expression uses lazy quantifying, because I need the expression to match as many characters as there are leading up to the photo number or file extension. If I wouldn't use lazy quantification, the expression would capture everything and then backtrack, measuring against the lookahead, at which point it would always succeed first on the '.jpg' file extension.

However, when using a lazy quantifier, the engine will match a character and check the lookahead before matching the next character. That way, if there is an underscore in the file name, the expression will match and return.

Submitted by Mendel Groner