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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

"
"
ig

Test String

Code Generator

Language

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?i)(?<if>#if\((?<ifContents>[^\)]+)\))(?<ifResult>[\s\S]+?)(?=#elif|#else|#end)(?<elIf>#elif[\s\S]+?(?=#else|#end))?(?<else>#else([\s\S]+?(?=#end)))?[\s\S]*?#end" Local $sString = "NOTE: because regex doesn't support multiple captures with 1 group the 'elif' part will be parsed in part 2." & @CRLF & _ "" & @CRLF & _ "Ignore" & @CRLF & _ "" & @CRLF & _ " #if(#C.Age >= 18)" & @CRLF & _ " 18+ lesgo" & @CRLF & _ " #end" & @CRLF & _ "" & @CRLF & _ "Ignore" & @CRLF & _ "" & @CRLF & _ " #if(#C.Age >= 18)" & @CRLF & _ " 18+ lesgo" & @CRLF & _ " #else" & @CRLF & _ " No special thingy" & @CRLF & _ " #end" & @CRLF & _ "" & @CRLF & _ "Ignore" & @CRLF & _ "" & @CRLF & _ " #if(#C.Age >= 18)" & @CRLF & _ " 18+ lesgo" & @CRLF & _ " #elif(#C.Length >= 1.9m)" & @CRLF & _ " Tall boi" & @CRLF & _ " #elif(#C.Name == bob)" & @CRLF & _ " Hi bob" & @CRLF & _ " #else" & @CRLF & _ " No special thingy" & @CRLF & _ " #end" & @CRLF & _ "" & @CRLF & _ "Ignore" & @CRLF & _ "" & @CRLF & _ " #if(#C.Age >= 18)18+ lesgo #elif(#C.Length >= 1.9m)Tall boi#elif(#C.Name == bob)Hi bob #elseNo special thingy#end" & @CRLF & _ "" & @CRLF & _ "Ignore" 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