Regular Expressions 101

Save & Share

  • Regex Version: ver. 4
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = '{"version":2,"(sectionConfig)":{"SECT:1236":{"children":{"ELE:1826":{"children":{"ELE:4217":{"(isHidden)":true},"ELE:22043":{"isHidden":true},"ELE:4253":{"isHidden":true},"ELE:1796":{"isHidden":true},"ELE:3907":{"isHidden":true}},"defaultSelectionId":"ELE:1781"},"ELE:1850":{"defaultSelectionId":"ELE:2657"},"ELE:1832":{"children":{"ELE:602":{"isHidden":true},"ELE:3864":{"isHidden":true},"ELE:650":{"isHidden":true}},"defaultSelectionId":"ELE:605"},"ELE:3711":{"isHidden":true}}},"SECT:2789":{"children":{"ELE:3923":{"isHidden":true},"ELE:3932":{"isHidden":true},"ELE:3920":{"isHidden":true},"ELE:3929":{"isHidden":true},"ELE:3938":{"isHidden":true},"ELE:3917":{"isHidden":true},"ELE:3926":{"isHidden":true},"ELE:3935":{"isHidden":true},"ELE:2834":{"isHidden":true},"ELE:2837":{"isHidden":true},"ELE:2960":{"isHidden":true},"ELE:2675":{"isHidden":true},"ELE:2933":{"isHidden":true},"ELE:2690":{"isHidden":true},"ELE:2717":{"isHidden":true},"ELE:3011":{"isHidden":true},"ELE:2681":{"isHidden":true},"ELE:2723":{"isHidden":true},"ELE:2693":{"isHidden":true},"ELE:2795":{"isHidden":true},"ELE:3014":{"isHidden":true},"ELE:2708":{"isHidden":true},"ELE:2975":{"isHidden":true},"ELE:2729":{"isHidden":true},"ELE:2996":{"isHidden":true},"ELE:2987":{"isHidden":true},"ELE:2672":{"isHidden":true},"ELE:2684":{"isHidden":true},"ELE:2669":{"isHidden":true}}},"SECT:2531":{"children":{"ELE:1862":{"children":{"ELE:26661":{"isHidden":true},"ELE:26682":{"isHidden":true},"ELE:26631":{"isHidden":true},"ELE:26601":{"isHidden":true}},"defaultSelectionId":"ELE:647"},"ELE:2690":{"isHidden":true},"ELE:2637":{"isHidden":true},"ELE:2485":{"isHidden":true},"ELE:1832":{"children":{"ELE:650":{"isHidden":true},"ELE:602":{"isHidden":true}},"defaultSelectionId":"ELE:605"},"ELE:2599":{"isHidden":true},"ELE:2521":{"isHidden":true},"ELE:1826":{"children":{"ELE:27478":{"isHidden":true},"ELE:27469":{"isHidden":true},"ELE:27460":{"isHidden":true},"ELE:27445":{"isHidden":true},"ELE:27436":{"isHidden":true},"ELE:27427":{"isHidden":true},"ELE:1796":{"isHidden":true},"ELE:4217":{"isHidden":true},"ELE:22043":{"isHidden":true},"ELE:27115":{"isHidden":true},"ELE:3907":{"isHidden":true}},"defaultSelectionId":"ELE:1781"}}}}} regexEdit tags'; my $regex = qr/(?<="ELE:)\d+(?=":{"isHidden":true})/mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html