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

r"
"
gx

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 $sRegex = "(?x)(?:\s|^) # Start of string or word boundary" & @CRLF & _ "( # Capture Group" & @CRLF & _ "(?: # Non-Capture Group for X." & @CRLF & _ "(?: # Nested NCG for 0..255" & @CRLF & _ "(?:\d){1,2}| # Allow any single digit or any pair of digits or" & @CRLF & _ "(?:1\d{2})| # 3 Digits starting with 1 or" & @CRLF & _ "(?:2[0-4]\d)| # 3 Digists starting with 20..24 or" & @CRLF & _ "(?:25[0-5]) # 250..255" & @CRLF & _ ") # this should allow X=0..255 in the NCG" & @CRLF & _ "\. # Must be followed by a literal ." & @CRLF & _ "){3} # X. Must repeat exactly 3 times" & @CRLF & _ "(?: # NCG for final 0..255" & @CRLF & _ "(?:\d{1,2})| # Allow any single digit or any pair of digits or" & @CRLF & _ "(?:1\d{2})| # 3 Digits starting with 1 or" & @CRLF & _ "(?:2[0-4]\d)| # 3 digits starting 20..24 or" & @CRLF & _ "(?:25[0-5]) # 250.255" & @CRLF & _ ") # End of final 0.255" & @CRLF & _ ") # End of capture group" & @CRLF & _ "(?:\s|$) # Must be followed by EOS or wspace" Local $sString = "123.123.123.145 is an IP4 so is 1.2.3.4 and 1.22.33.44 but 256.1.2.3 isn't 254.1.2.3 is but 260.1.1.1 isn't nor 2.5.256.1 and 1.2.3.4:222 IP6 1.2.3.4.5.6" 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