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

/
/
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 $sRegex = "(?m)^([A-Z](([A-Z]{1,2}[a-z0-9]+)+([A-Z]{1,3}[a-z0-9]+)*[A-Z]{0,3}|([a-z0-9]+[A-Z]{0,3})*|[A-Z]{1,2}))$|^([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 = "ABCD" & @CRLF & _ "ABCDE" & @CRLF & _ "MdeADFAFdsADFads" & @CRLF & _ "DeviceSNSD" & @CRLF & _ "AabcABCD" & @CRLF & _ "ABabcABCD" & @CRLF & _ "ABabcABCDabcABCD" & @CRLF & _ "ABCabcABCD" & @CRLF & _ "ABCabcABCDabcABCDabcABCDabcABCD" & @CRLF & _ "ABCDabcABCD" & @CRLF & _ "ABCDabcABCDabcABCDabcABCDabcABCD" & @CRLF & _ "HTMLParser" & @CRLF & _ "ContextHTMLParser" & @CRLF & _ "ABCDabcABC" & @CRLF & _ "ABCDabcAB" & @CRLF & _ "ABCDabcA" & @CRLF & _ "CamelCa_1" & @CRLF & _ "HELLO" & @CRLF & _ "snake_case" & @CRLF & _ "2PascalCase" & @CRLF & _ "streamIOIO" & @CRLF & _ "gREATERDtha" & @CRLF & _ "modeADFAFdsADFads" & @CRLF & _ "camelCa_1" & @CRLF & _ "contextHTMLParser" & @CRLF & _ "hELLO" & @CRLF & _ "AabcABCDabcABC" & @CRLF & _ "AabcABCDabcABCD" & @CRLF & _ "AabcABCabcABCD" & @CRLF & _ "ABabcABCDabcABC" & @CRLF & _ "ABabcABCDabcABCD" & @CRLF & _ "ABabcABCabcABCD" & @CRLF & _ "aBabcABCDabcABC" & @CRLF & _ "aBabcABCDabcABCD" & @CRLF & _ "aBabcABCabcABCD" & @CRLF & _ "ababcABCDabcABC" & @CRLF & _ "ababcABCDabcABCD" & @CRLF & _ "ababcABCabcABCD" & @CRLF & _ "SerialNO" & @CRLF & _ "serialNo" & @CRLF & _ "context" & @CRLF & _ "camelCasE" & @CRLF & _ "aGa" & @CRLF & _ "alphabet" & @CRLF & _ "serialNO" & @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" & @CRLF & _ "Ag" & @CRLF & _ "ABCabcABCabc" & @CRLF & _ "AwsVPC" & @CRLF & _ "AaABC" & @CRLF & _ "PacalCasePacalCasePacalCasePacalCasePacalCasePacalCase" & @CRLF & _ "AabcABCabcABC" & @CRLF & _ "MoeADFdsADFads" & @CRLF & _ "ABCabcABC" & @CRLF & _ "ABCabcAB" & @CRLF & _ "ABabcABC" & @CRLF & _ "ABabcAB" & @CRLF & _ "AabcAB" & @CRLF & _ "ABCabcABCabcA" & @CRLF & _ "ABCabcA" & @CRLF & _ "Aabc123" & @CRLF & _ "AabcABC" & @CRLF & _ "A" & @CRLF & _ "AB" & @CRLF & _ "ABC" & @CRLF & _ "StreamIO" & @CRLF & _ "IOStream" & @CRLF & _ "DeviceID" & @CRLF & _ "DeviceSNS" & @CRLF & _ "Context" & @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