Regular Expressions 101

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  • Unit Tests (9)

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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"
"
xs

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 = "(?xs)^(?P<timestamp>.{19})\ \[(?P<severity>\w{4,6})\]" & @CRLF & _ "\ \d+\#\d+:\ (\*\d+\ )?" & @CRLF & _ "(?P<err_msg>" & @CRLF & _ " (?:\"\S+\"\sis\snot\s)?" & @CRLF & _ " (?P<err_type>\w+)[\s(] " & @CRLF & _ " (?:requests,\ excess:\ (?P<err_rate>\d+\.\d+)" & @CRLF & _ " \ by\ zone\ \"(?P<err_zone>\S+)\"" & @CRLF & _ " |.+?)" & @CRLF & _ ")" & @CRLF & _ "(?:" & @CRLF & _ " ,\ client:\ (?P<remote_addr>\d+\.\d+\.\d+\.\d+)" & @CRLF & _ " ,\ server:\ (?P<server>[^,\a]+)" & @CRLF & _ " (?:,\ request:\ \"(?P<method>[A-Z]{3,4}?)" & @CRLF & _ " \ (?P<uri>\/\S*?)(?P<uri_query>\?\S+)?" & @CRLF & _ " \ (?P<protocol>\S+)\"" & @CRLF & _ " )?" & @CRLF & _ " (?:,\ upstream:\ \"(?P<upstream>.+?)\")?" & @CRLF & _ " (?:,\ host:\ \"(?P<req_host>\S+)\")?" & @CRLF & _ " (?:,\ referrer:\ \"(?P<referrer>\S+)\")?" & @CRLF & _ "|)" & @CRLF & _ "$" Local $sString = "2023/06/16 17:12:30 [error] 1814859#1814859: *228570402 limiting requests, excess: 50.120 by zone "resizerzone", client: 10.5.0.122, server: app.market.com, request: "GET /resizer/view?key=8e158c8741ce849a09ef84d316bb68e7&b=productimages&f=webp&s=0 HTTP/1.1", host: "market.com", referrer: "https://market.com/"" & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYFULLMATCH) ; Present the entire match result _ArrayDisplay($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