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

/
/
gmx

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 = "(?mx)^" & @CRLF & _ "(?P<group>" & @CRLF & _ " (?P<structured>" & @CRLF & _ " (?P<single>" & @CRLF & _ " (?P<tag_first>" & @CRLF & _ " (?P<tag>" & @CRLF & _ " \d+(?:\/\d+)+" & @CRLF & _ " |" & @CRLF & _ " (?P<repnum>\$+(?:@\^*-?\d*)?)" & @CRLF & _ " |" & @CRLF & _ " [\w:!-]" & @CRLF & _ " )++" & @CRLF & _ " (?P<attr>" & @CRLF & _ " (?P<short_attr>" & @CRLF & _ " \." & @CRLF & _ " (?P<short_val>" & @CRLF & _ " (?P>repnum)" & @CRLF & _ " |" & @CRLF & _ " [\w:!-]" & @CRLF & _ " )*" & @CRLF & _ " |" & @CRLF & _ " \#(?P>short_val)*" & @CRLF & _ " )" & @CRLF & _ " |" & @CRLF & _ " (?P<long_attr>" & @CRLF & _ " \[" & @CRLF & _ " (?P<attr_pair>" & @CRLF & _ " (?P<attr_name>" & @CRLF & _ " \\(?:\\{2})*["'\s]" & @CRLF & _ " |" & @CRLF & _ " [^\[\]"'\s\\]" & @CRLF & _ " )+" & @CRLF & _ " \.?" & @CRLF & _ " (?P<equal_val>" & @CRLF & _ " =" & @CRLF & _ " (?P<attr_val>" & @CRLF & _ " (?P<unquoted_val>" & @CRLF & _ " \\(?:\\{2})*[\[\]"'\s]" & @CRLF & _ " |" & @CRLF & _ " [^\[\]"'\s\\]" & @CRLF & _ " )+" & @CRLF & _ " |" & @CRLF & _ " (?P<quoted_val>" & @CRLF & _ " (?P<quote>["'])" & @CRLF & _ " (?:" & @CRLF & _ " (?P<escaped_all>\\(?:\\{2})*.)" & @CRLF & _ " |" & @CRLF & _ " [^"'\n\\]" & @CRLF & _ " )*" & @CRLF & _ " (?P=quote)" & @CRLF & _ " )" & @CRLF & _ " )?" & @CRLF & _ " )?" & @CRLF & _ " )?" & @CRLF & _ " (?:\s+(?P>attr_pair))*" & @CRLF & _ " \]" & @CRLF & _ " )" & @CRLF & _ " )*" & @CRLF & _ " |" & @CRLF & _ " (?P>attr)+" & @CRLF & _ " )" & @CRLF & _ " (?P<tag_rest>" & @CRLF & _ " (?P<text>" & @CRLF & _ " \{" & @CRLF & _ " (?P<text_content>" & @CRLF & _ " (?P>escaped_all)" & @CRLF & _ " |" & @CRLF & _ " [^{}\n\\]" & @CRLF & _ " )*" & @CRLF & _ " \}" & @CRLF & _ " )" & @CRLF & _ " (?P>attr)*" & @CRLF & _ " (?:" & @CRLF & _ " (?P<rep>\*\d*+)?" & @CRLF & _ " (?P>attr)*" & @CRLF & _ " (?P<close>\/)?" & @CRLF & _ " |" & @CRLF & _ " (?P>close)?" & @CRLF & _ " (?P>rep)?" & @CRLF & _ " )" & @CRLF & _ " |" & @CRLF & _ " (?P>rep)" & @CRLF & _ " (?P>attr)*" & @CRLF & _ " (?P>text)?" & @CRLF & _ " (?P>attr)*" & @CRLF & _ " (?P>close)?" & @CRLF & _ " |" & @CRLF & _ " (?P>close)" & @CRLF & _ " (?P>rep)?" & @CRLF & _ " )?" & @CRLF & _ " |" & @CRLF & _ " (?P<text_first>(?P>text)(?P>attr)*)" & @CRLF & _ " (?P<text_rest>" & @CRLF & _ " (?P>rep)" & @CRLF & _ " (?P>attr)*" & @CRLF & _ " (?P>close)?" & @CRLF & _ " |" & @CRLF & _ " (?P>close)" & @CRLF & _ " (?P>rep)?" & @CRLF & _ " )?" & @CRLF & _ " )" & @CRLF & _ " (?:" & @CRLF & _ " (?P<relation>[>+]|\^+)" & @CRLF & _ " (?P>group)*" & @CRLF & _ " )?" & @CRLF & _ " )" & @CRLF & _ "|" & @CRLF & _ " \(" & @CRLF & _ " (?P>group)*" & @CRLF & _ " \)" & @CRLF & _ " (?P>rep)?" & @CRLF & _ " (?P>relation)?" & @CRLF & _ ")+" & @CRLF & _ "$" Local $sString = ">>> tag <<<" & @CRLF & _ "tag" & @CRLF & _ "$" & @CRLF & _ "tag$with$@^^^-2repnum" & @CRLF & _ "1" & @CRLF & _ "1/2" & @CRLF & _ "1/2/3" & @CRLF & _ "tag1/2with1/2/3fraction" & @CRLF & _ "tag$@with1/2both" & @CRLF & _ "ri:a" & @CRLF & _ "!" & @CRLF & _ "!!!" & @CRLF & _ "-" & @CRLF & _ ":" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ "@" & @CRLF & _ "&" & @CRLF & _ "" & @CRLF & _ ">>> short attr <<<" & @CRLF & _ "#" & @CRLF & _ "###" & @CRLF & _ "#id" & @CRLF & _ "#id1#id2" & @CRLF & _ "#id$@^^^-2" & @CRLF & _ "." & @CRLF & _ ".#" & @CRLF & _ "..." & @CRLF & _ ".class" & @CRLF & _ ".class1.class2" & @CRLF & _ ".class#id.class" & @CRLF & _ ".class$@^-2type" & @CRLF & _ ".class-data" & @CRLF & _ ".!class" & @CRLF & _ ".class:subclass" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ ".@" & @CRLF & _ ".汉字" & @CRLF & _ "" & @CRLF & _ ">>> long attr <<<" & @CRLF & _ "[]" & @CRLF & _ "[key]" & @CRLF & _ "[key.]" & @CRLF & _ "[key...]" & @CRLF & _ "[key=]" & @CRLF & _ "[key.=]" & @CRLF & _ "[key=val]" & @CRLF & _ "[key.=val]" & @CRLF & _ "[key='val']" & @CRLF & _ "[key='val with space']" & @CRLF & _ "[key='val\\\'ue']" & @CRLF & _ "[key1=val1 key2=val2]" & @CRLF & _ "[][]" & @CRLF & _ "[key][key]" & @CRLF & _ ".class[key]" & @CRLF & _ "[key].class" & @CRLF & _ "[汉字=汉字]" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ "[\[]" & @CRLF & _ "[key='val\\'ue']" & @CRLF & _ "" & @CRLF & _ ">>> text <<<" & @CRLF & _ "{}" & @CRLF & _ "{text}" & @CRLF & _ "{text with space}" & @CRLF & _ "{text with escaped \{ and \}}" & @CRLF & _ "{汉字}" & @CRLF & _ "tag{text}" & @CRLF & _ ".attr{text}" & @CRLF & _ "{text}.attr" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ "{\\{}" & @CRLF & _ "{{}}" & @CRLF & _ "" & @CRLF & _ ">>> repeater <<<" & @CRLF & _ "tag*2" & @CRLF & _ ".attr*2" & @CRLF & _ "{text}*2" & @CRLF & _ ".attr{text}*2" & @CRLF & _ ".attr{text}.attr*2" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ "*2" & @CRLF & _ "tag*2*2" & @CRLF & _ "" & @CRLF & _ ">>> self-close <<<" & @CRLF & _ "tag/" & @CRLF & _ ".attr/" & @CRLF & _ "{text}/" & @CRLF & _ "tag*2/" & @CRLF & _ "tag/*2" & @CRLF & _ ".attr{text}.attr/" & @CRLF & _ ".attr*2.attr{text}.attr/" & @CRLF & _ ".attr{text}.attr*2.attr/" & @CRLF & _ ".attr{text}/*2" & @CRLF & _ "tag*2{text}/" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ "/*2" & @CRLF & _ "tag//" & @CRLF & _ "" & @CRLF & _ ">>> child <<<" & @CRLF & _ "tag>tag" & @CRLF & _ "tag.class*2>tag[key]/" & @CRLF & _ "tag>" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ ">tag" & @CRLF & _ "tag>>" & @CRLF & _ "" & @CRLF & _ ">>> sibling <<<" & @CRLF & _ "tag+tag" & @CRLF & _ ".class/>[key]+.attr/*2" & @CRLF & _ "tag[key]tag" & @CRLF & _ "tag{text}tag" & @CRLF & _ "tag*2tag" & @CRLF & _ "tag/tag" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ "+tag" & @CRLF & _ "tag++" & @CRLF & _ "" & @CRLF & _ ">>> parent <<<" & @CRLF & _ "tag^tag" & @CRLF & _ "tag^^^" & @CRLF & _ "tag>tag+tag^tag" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ "^tag" & @CRLF & _ "" & @CRLF & _ ">>> group <<<" & @CRLF & _ "()" & @CRLF & _ "(())" & @CRLF & _ "(tag)" & @CRLF & _ "(tag)(tag)" & @CRLF & _ "((tag)(tag))" & @CRLF & _ "tag>(tag.class)" & @CRLF & _ "tag>(tag>tag+tag)" & @CRLF & _ "(tag>(tag+tag)*2)*2" & @CRLF & _ "(tag)tag" & @CRLF & _ "(tag>).class" & @CRLF & _ "(tag)*2^tag" & @CRLF & _ "(tag*2)^tag" & @CRLF & _ "(tag>)^tag" & @CRLF & _ "(tag)^" & @CRLF & _ "" & @CRLF & _ "===XXX===" & @CRLF & _ "(" & @CRLF & _ "(()" 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