Regular Expressions 101

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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
Processing...

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 $sRegex = "(?xis)(?(DEFINE)" & @CRLF & _ " (?<XHTML>" & @CRLF & _ " (?&comment)*\s*" & @CRLF & _ " (?&DOCTYPE)" & @CRLF & _ " (?&comment)*\s*" & @CRLF & _ " (?&HTML)" & @CRLF & _ " (?&comment)*\s*" & @CRLF & _ " )" & @CRLF & _ "" & @CRLF & _ " # HTML element" & @CRLF & _ " (?<HTML>" & @CRLF & _ " <html(?&attrs)?>(?&content)<\/html>" & @CRLF & _ " )" & @CRLF & _ "" & @CRLF & _ " # Match content" & @CRLF & _ " (?<content>" & @CRLF & _ " \s*" & @CRLF & _ " (?:" & @CRLF & _ " ((?&tag) | [^<>]+)\s*" & @CRLF & _ " )*" & @CRLF & _ " )" & @CRLF & _ "" & @CRLF & _ " # General tag" & @CRLF & _ " (?<tag>" & @CRLF & _ " <((?&tagname))(?&attrs)?\s*(?:" & @CRLF & _ " \/>|" & @CRLF & _ " >\s*(?&content)\s*" & @CRLF & _ " <\/\g'-1'>" & @CRLF & _ " )|(?&comment)" & @CRLF & _ " )" & @CRLF & _ "" & @CRLF & _ " # Attributes" & @CRLF & _ " (?<attrs>\s+" & @CRLF & _ " # The name" & @CRLF & _ " (?&keyword) (" & @CRLF & _ " \s*=\s*" & @CRLF & _ " (?:" & @CRLF & _ " (?&keyword)|(?&string)" & @CRLF & _ " )" & @CRLF & _ " )?" & @CRLF & _ " (?&attrs)?" & @CRLF & _ " )" & @CRLF & _ "" & @CRLF & _ " (?<string>" & @CRLF & _ " "(?:\\.|.)+?"|" & @CRLF & _ " '(?:\\.|.)+?'" & @CRLF & _ " )" & @CRLF & _ "" & @CRLF & _ " (?<comment>" & @CRLF & _ " \s*<!--(.+?)-->\s*" & @CRLF & _ " )" & @CRLF & _ "" & @CRLF & _ " # Match keyword" & @CRLF & _ " (?<keyword>[^\s\/>"'=]+)" & @CRLF & _ " # Match tag name" & @CRLF & _ " (?<tagname>(?!xml)[A-Za-z_][A-Za-z\d_.-]*)" & @CRLF & _ "" & @CRLF & _ " # DOCTYPE expression" & @CRLF & _ " (?<DOCTYPE>" & @CRLF & _ " <!doctype\s+x?html\s*(public\s*(?&string))?(\s+(?&string))*>" & @CRLF & _ " )" & @CRLF & _ ")" & @CRLF & _ "" & @CRLF & _ "^\s*(?&XHTML)\s*$" Local $sString = "<!-- test -->" & @CRLF & _ "<!DOCTYPE html " & @CRLF & _ " PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN"" & @CRLF & _ " "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">" & @CRLF & _ " <html goat:style="''inva'lid css I know">textttt<head></head><body><div class="onfoodstamps"><div class="upper">foo<p>ayyy</p>bar</div>baz</div><br/></head></html>" 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