Regular Expressions 101

Save & Share

  • Regex Version: ver. 3
  • 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

Substitution

Processing...

Code Generator

Language

Generated Code

#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox Local $sRegex = "(?m)^(\s*)(?!window\.)(\w+\.)?(\w+)(\s*)([:=])(\s*)function(\s*)\(" Local $sString = "this.foo = function() { // this.foo = function foo() {" & @CRLF & _ "something.foo : function() { // something.foo : function foo() {" & @CRLF & _ "window.foo = function() { // window.foo = function() {" & @CRLF & _ "this.foo[i] : function() { // this.foo[i] : function() {" & @CRLF & _ "" & @CRLF & _ "var foo = function() { // var foo = function foo() {" & @CRLF & _ "" & @CRLF & _ "foo: function() { // foo: function foo() {" & @CRLF & _ "foo :function() { // foo :function foo() {" & @CRLF & _ "foo:function() { // foo:function foo() {" & @CRLF & _ "foo : function() { // foo : function foo() {" & @CRLF & _ "" & @CRLF & _ "foo = function() { // foo = function foo() {" & @CRLF & _ "" & @CRLF & _ "foo = function () {} // foo = function foo () {}" & @CRLF & _ "" & @CRLF & _ " foo = function() { // foo = function foo() {" Local $sSubst = "$1$2$3$4$5$6function $3$7(" Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst) MsgBox($MB_SYSTEMMODAL, "Result", $sResult)

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