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

/
/
gm

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 $sRegex = "(?m)^[ \t]*([0]|([-+]?(\d*\.)?\d+)(cm|mm|in|px|pt|pc|Q|em|ex|ch|rem|vw|vh|vmin|vmax|%)){1}([\t ]+([0]|([-+]?(\d*\.)?\d+)(cm|mm|in|px|pt|pc|Q|em|ex|ch|rem|vw|vh|vmin|vmax|%))){0,3}[\t ]*$" Local $sString = "0" & @CRLF & _ " 0 " & @CRLF & _ "0px" & @CRLF & _ " 0px 0px 0px 0" & @CRLF & _ "0 0" & @CRLF & _ " 0cm 0px 0ch 0% " & @CRLF & _ " 0 0 " & @CRLF & _ "0 0 0" & @CRLF & _ " 0 0 0 " & @CRLF & _ "0 0 0 0" & @CRLF & _ "2px 0" & @CRLF & _ "+2px" & @CRLF & _ "-3px" & @CRLF & _ "0 2px" & @CRLF & _ " 3cm " & @CRLF & _ "0px" & @CRLF & _ "0px 0px 0px" & @CRLF & _ " 1px " & @CRLF & _ " 2px 2px " & @CRLF & _ " 3px 3px 3px " & @CRLF & _ " 4px 4px 4px 4px " & @CRLF & _ "+4px -4px -4px +4px " & @CRLF & _ "-1px " & @CRLF & _ " -2px -2px " & @CRLF & _ " -3px -3px -3px " & @CRLF & _ " -4px -4px -4px -4px " & @CRLF & _ "1% " & @CRLF & _ " 2% 2vh " & @CRLF & _ " 3vw 3vh 3% " & @CRLF & _ " 4cm 4pt -4vmin 4vmax " & @CRLF & _ "" & @CRLF & _ "# Errors - must not match" & @CRLF & _ " " & @CRLF & _ "00" & @CRLF & _ "0 0px 00 " & @CRLF & _ "1px-2px " & @CRLF & _ " 2px2px " & @CRLF & _ " 3pxf 3px 3px sdsd" & @CRLF & _ " 4px-4px 4px 4px " & @CRLF & _ "4px4px4px4px " & @CRLF & _ "4px 4px 4px 4-px " & @CRLF & _ "-4px-4px-4px-4px " & @CRLF & _ "--3px" & @CRLF & _ "+-3px" & @CRLF & _ "-4px-4px -4px- 4px " & @CRLF & _ "-4" & @CRLF & _ "+5" & @CRLF & _ "+0px -0" & @CRLF & _ "+0" 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