Regular Expressions 101

Save & Share

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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gm

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)^(?P<major>0|[1-9]\d*)\.(?P<minor>0|[1-9]\d*)\.(?P<patch>0|[1-9]\d*)(?:-(?P<prerelease>(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+(?P<buildmetadata>[0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$" Local $sString = "Valid Semantic Versions" & @CRLF & _ "Source: https://semver.org" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "0.0.4" & @CRLF & _ "1.2.3" & @CRLF & _ "10.20.30" & @CRLF & _ "1.1.2-prerelease+meta" & @CRLF & _ "1.1.2+meta" & @CRLF & _ "1.1.2+meta-valid" & @CRLF & _ "1.0.0-alpha" & @CRLF & _ "1.0.0-beta" & @CRLF & _ "1.0.0-alpha.beta" & @CRLF & _ "1.0.0-alpha.beta.1" & @CRLF & _ "1.0.0-alpha.1" & @CRLF & _ "1.0.0-alpha0.valid" & @CRLF & _ "1.0.0-alpha.0valid" & @CRLF & _ "1.0.0-alpha-a.b-c-somethinglong+build.1-aef.1-its-okay" & @CRLF & _ "1.0.0-rc.1+build.1" & @CRLF & _ "2.0.0-rc.1+build.123" & @CRLF & _ "1.2.3-beta" & @CRLF & _ "10.2.3-DEV-SNAPSHOT" & @CRLF & _ "1.2.3-SNAPSHOT-123" & @CRLF & _ "1.0.0" & @CRLF & _ "2.0.0" & @CRLF & _ "1.1.7" & @CRLF & _ "2.0.0+build.1848" & @CRLF & _ "2.0.1-alpha.1227" & @CRLF & _ "1.0.0-alpha+beta" & @CRLF & _ "1.2.3----RC-SNAPSHOT.12.9.1--.12+788" & @CRLF & _ "1.2.3----R-S.12.9.1--.12+meta" & @CRLF & _ "1.2.3----RC-SNAPSHOT.12.9.1--.12" & @CRLF & _ "1.0.0+0.build.1-rc.10000aaa-kk-0.1" & @CRLF & _ "99999999999999999999999.999999999999999999.99999999999999999" & @CRLF & _ "1.0.0-0A.is.legal" & @CRLF & _ "" & @CRLF & _ "Invalid Semantic Versions" & @CRLF & _ "" & @CRLF & _ "1" & @CRLF & _ "1.2" & @CRLF & _ "1.2.3-0123" & @CRLF & _ "1.2.3-0123.0123" & @CRLF & _ "1.1.2+.123" & @CRLF & _ "+invalid" & @CRLF & _ "-invalid" & @CRLF & _ "-invalid+invalid" & @CRLF & _ "-invalid.01" & @CRLF & _ "alpha" & @CRLF & _ "alpha.beta" & @CRLF & _ "alpha.beta.1" & @CRLF & _ "alpha.1" & @CRLF & _ "alpha+beta" & @CRLF & _ "alpha_beta" & @CRLF & _ "alpha." & @CRLF & _ "alpha.." & @CRLF & _ "beta" & @CRLF & _ "1.0.0-alpha_beta" & @CRLF & _ "-alpha." & @CRLF & _ "1.0.0-alpha.." & @CRLF & _ "1.0.0-alpha..1" & @CRLF & _ "1.0.0-alpha...1" & @CRLF & _ "1.0.0-alpha....1" & @CRLF & _ "1.0.0-alpha.....1" & @CRLF & _ "1.0.0-alpha......1" & @CRLF & _ "1.0.0-alpha.......1" & @CRLF & _ "01.1.1" & @CRLF & _ "1.01.1" & @CRLF & _ "1.1.01" & @CRLF & _ "1.2" & @CRLF & _ "1.2.3.DEV" & @CRLF & _ "1.2-SNAPSHOT" & @CRLF & _ "1.2.31.2.3----RC-SNAPSHOT.12.09.1--..12+788" & @CRLF & _ "1.2-RC-SNAPSHOT" & @CRLF & _ "-1.0.3-gamma+b7718" & @CRLF & _ "+justmeta" & @CRLF & _ "9.8.7+meta+meta" & @CRLF & _ "9.8.7-whatever+meta+meta" & @CRLF & _ "99999999999999999999999.999999999999999999.99999999999999999----RC-SNAPSHOT.12.09.1--------------------------------..12" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm