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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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 $sRegex = "(?m)^[a-z][a-z0-9]*(([A-Z]{1,3}[a-z0-9]+)*[A-Z]{0,3}|([a-z0-9]+[A-Z]{1,3})*|[A-Z]{1,3})$" Local $sString = "snake_case" & @CRLF & _ "PascalCase" & @CRLF & _ "2PascalCase" & @CRLF & _ "streamIOIO" & @CRLF & _ "gREATERDtha" & @CRLF & _ "modeADFAFdsADFads" & @CRLF & _ "aBabcABCDabcABC" & @CRLF & _ "camelCa_1" & @CRLF & _ "contextHTMLParser" & @CRLF & _ "hELLO" & @CRLF & _ "modeADFdsADFads" & @CRLF & _ "streamIO" & @CRLF & _ "aBCabcABCabcA" & @CRLF & _ "aBCabcA" & @CRLF & _ "aabc123" & @CRLF & _ "aabcABC" & @CRLF & _ "ab" & @CRLF & _ "abc" & @CRLF & _ "abcd" & @CRLF & _ "abcde" & @CRLF & _ "deviceSNS" & @CRLF & _ "pathASNs" & @CRLF & _ "dscpCP" & @CRLF & _ "awsVPC" & @CRLF & _ "deviceID" & @CRLF & _ "camelCasecamelCasecamelCasecamelCasecamelCasecamelCase" & @CRLF & _ "gREA1" & @CRLF & _ "gREAt" & @CRLF & _ "gREAtREAt" & @CRLF & _ "cP3" & @CRLF & _ "a1" & @CRLF & _ "aABC" & @CRLF & _ "a123" & @CRLF & _ "modeADFsADFads" & @CRLF & _ "a1G" & @CRLF & _ "aG" & @CRLF & _ "a" & @CRLF & _ "modeADFads" & @CRLF & _ "camelCase" & @CRLF & _ "lThan30DaysCount" & @CRLF & _ "lessThan30DaysCount" & @CRLF & _ "lessThan30DaysCountA" & @CRLF & _ "greaterThan30LessThan60DaysCount" & @CRLF & _ "greaterThan60LessThan90DaysCount" & @CRLF & _ "greaterThan90DaysCount" & @CRLF & _ "pascalCase" & @CRLF & _ "pascal2Case" & @CRLF & _ "pascalCaseA" & @CRLF & _ "pascal2CaseA" & @CRLF & _ "modeA" & @CRLF & _ "mode2A" & @CRLF & _ "mode2A2" & @CRLF & _ "mode2A2A" & @CRLF & _ "createAMode" & @CRLF & _ "createBMode" & @CRLF & _ "madeEasy" & @CRLF & _ "wonderFul" & @CRLF & _ "andMe" & @CRLF & _ "htmlParser" & @CRLF & _ "h" & @CRLF & _ "aaA" & @CRLF & _ "camel01C" & @CRLF & _ "camel01c01" & @CRLF & _ "camel01C01" & @CRLF & _ "camel01CC01" & @CRLF & _ "camel0a1c1" & @CRLF & _ "camel0a1C1" & @CRLF & _ "camel0ac1b1C1" & @CRLF & _ "camelC" & @CRLF & _ "camelC1" & @CRLF & _ "camelCA" & @CRLF & _ "camelCa1" & @CRLF & _ "ibsReleaseTestVerificationRegressionSuite" & @CRLF & _ "ibsReleaseTestVerificationRegressioNSuite" & @CRLF & _ "ibsReleaseTestVerificationRegressioN" & @CRLF & _ "xmlHttpRequest" & @CRLF & _ "newCustomerId" & @CRLF & _ "innerStopwatch" & @CRLF & _ "supportsIpv6OnIos" & @CRLF & _ "youTubeImporter" & @CRLF & _ "youtubeImporter" & @CRLF & _ "affine3D" 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