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
  • 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

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)^((?:[A-Za-z0-9!#$%&'*+\-\/=?^_`{|}~]|(?<=^|\.)"|"(?=$|\.|@)|(?<=".*)[ .](?=.*")|(?<!\.)\.){1,64})(@)((?:[A-Za-z0-9.\-])*(?:[A-Za-z0-9])\.(?:[A-Za-z0-9]){2,})$" Local $sString = "Valid email addresses" & @CRLF & _ "" & @CRLF & _ "simple@example.com" & @CRLF & _ "" & @CRLF & _ "very.common@example.com" & @CRLF & _ "" & @CRLF & _ "disposable.style.email.with+symbol@example.com" & @CRLF & _ "" & @CRLF & _ "other.email-with-hyphen@example.com" & @CRLF & _ "" & @CRLF & _ "fully-qualified-domain@example.com" & @CRLF & _ "" & @CRLF & _ "user.name+tag+sorting@example.com" & @CRLF & _ "(may go to user.name@example.com inbox depending on mail server)" & @CRLF & _ "" & @CRLF & _ "x@example.com" & @CRLF & _ "(one-letter local-part)" & @CRLF & _ "" & @CRLF & _ "example-indeed@strange-example.com" & @CRLF & _ "" & @CRLF & _ "example@s.example" & @CRLF & _ "(see the List of Internet top-level domains)" & @CRLF & _ "" & @CRLF & _ "" "@example.org" & @CRLF & _ "(space between the quotes)" & @CRLF & _ "" & @CRLF & _ ""john..doe"@example.org" & @CRLF & _ "(quoted double dot)" & @CRLF & _ "" & @CRLF & _ "=============================================================" & @CRLF & _ "Invalid email addresses" & @CRLF & _ "" & @CRLF & _ "Abc.example.com" & @CRLF & _ "(no @ character)" & @CRLF & _ "" & @CRLF & _ "A@b@c@example.com" & @CRLF & _ "(only one @ is allowed outside quotation marks)" & @CRLF & _ "" & @CRLF & _ "a"b(c)d,e:f;g<h>i[j\k]l@example.com" & @CRLF & _ "(none of the special characters in this local-part are allowed outside quotation marks)" & @CRLF & _ "" & @CRLF & _ "just"not"right@example.com" & @CRLF & _ "(quoted strings must be dot separated or the only element making up the local-part)" & @CRLF & _ "" & @CRLF & _ "this is"not\allowed@example.com" & @CRLF & _ "(spaces, quotes, and backslashes may only exist when within quoted strings and preceded by a backslash)" & @CRLF & _ "" & @CRLF & _ "this\ still\"not\\allowed@example.com" & @CRLF & _ "(even if escaped (preceded by a backslash), spaces, quotes, and backslashes must still be contained by quotes)" & @CRLF & _ "" & @CRLF & _ "1234567890123456789012345678901234567890123456789012345678901234+x@example.com" & @CRLF & _ "(local part is longer than 64 characters)" 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