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
No Match

/
/
g

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 = "(\d+)\s+((?:[A-Za-zA-Z0-9]{0,3})+)\s+((?:[A-Za-z0-9\)\(\]\:\/<>\[\"\.\,\+\'\-]{2,} ?)+)\s+(\d{2,7}-\d{2}-\d)" Local $sString = "1 CH4 Methane 74-82-8" & @CRLF & _ "" & @CRLF & _ "2 C2H2 Ethyne 74-86-2" & @CRLF & _ "" & @CRLF & _ "5 C3H4 Propadiene 463-49-0" & @CRLF & _ "" & @CRLF & _ "6 C3H4 Propyne 74-99-7" & @CRLF & _ "" & @CRLF & _ "7 C3H6 Cyclopropane 75-19-4" & @CRLF & _ "" & @CRLF & _ "10 C4H2 Butadiyne, Diacetylene 460-12-8" & @CRLF & _ "" & @CRLF & _ "11 C4H4 1-Buten-3-yne, Vinylacetylene 689-97-4" & @CRLF & _ "" & @CRLF & _ "12 C4H6 1,2-Butadiene 590-19-2" & @CRLF & _ "" & @CRLF & _ "14 C4H6 Dibenzo[b,e]oxepine 107-00-6" & @CRLF & _ "" & @CRLF & _ "16 C4H6 Cyclobutene 822-35-5" & @CRLF & _ "" & @CRLF & _ "17 C4H8 1-Butene 106-98-9" & @CRLF & _ "" & @CRLF & _ "18 C4H8 (E)-2-Butene 624-64-6" & @CRLF & _ "" & @CRLF & _ "19 C4H8 (Z)-2-Butene 590-18-1" & @CRLF & _ "" & @CRLF & _ "22 C4H8 Pyrazolo[4',3':6,7]oxepino[4,5-b]indole 115-11-7" & @CRLF & _ "" & @CRLF & _ "23 C4H10 Butane 106-97-8" & @CRLF & _ "" & @CRLF & _ "27 C5H8 Bicyclo[2.1.0]pentane 185-94-4" & @CRLF & _ "" & @CRLF & _ "29 C5H8 3-Methyl-1-butyne 598-23-2" & @CRLF & _ "" & @CRLF & _ "35 C5H8 (E)-1,3-Pentadiene 2004-70-8" & @CRLF & _ "" & @CRLF & _ "41 C5H8 Spiro[2.2]pentane 157-40-4" & @CRLF & _ "" & @CRLF & _ "45 C5H10 cis-1,2-Dimethylcyclopropane 930-18-7" & @CRLF & _ "" & @CRLF & _ "66 C6H8 cis, anti, cis-Tricyclo[3.1.0.0(2,4)]hexane 21531-33-9" & @CRLF & _ "" & @CRLF & _ "70 C6H10 2,3-Dimethyl-1,3-butadiene 513-81-5" & @CRLF & _ "" & @CRLF & _ "71 C6H10 [1,1'-Binaphthalene]-3,3',4,4'-tetramine 513-81-5" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @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