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

/
/
igum

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 $sRegex = "(?ium)([-\.\w]+:\/{2,3})(?!.*[.]{2})(?![-.*\.])((?!.*@\.)[-_\w@^=%&:;~+\.]+(?<![-\.]))(\/[-_\w@^=%&:;/~+\.]+(?<!\.))?\??([-_\w=&@$!|~+]+)*#?([-_\w=&@$!|~+]+)*" Local $sString = "DB_URL=postgresql://postgres:postgres@localhost/postgres?timeout=0" & @CRLF & _ "# Damn, Daniel!" & @CRLF & _ "" & @CRLF & _ "Bob: have you checked https://www.facebook.com?" & @CRLF & _ "lorem https://github.com/justsml?tab=activity#top ipsum" & @CRLF & _ "smb:///winbox/dfs/ - ipp://printer" & @CRLF & _ "leading text chrome-extension://flags??#" & @CRLF & _ "s3://buckets/for/all?true=true" & @CRLF & _ "s3:///////buckets-o-fun" & @CRLF & _ "pkcs11://because-pkcs7-is-weak#only=hash" & @CRLF & _ "\||@@https://www.google.com <- should match when extracting" & @CRLF & _ "https://we - this is valid" & @CRLF & _ "s3://buckets-o-fun/!hi/raw=val&#keep=hashin'?" & @CRLF & _ "http://aaa.com.co.com:8080/test?dan=dev#den" & @CRLF & _ "hi. pkcs11://because-pkcs7-is-weak" & @CRLF & _ "hi. a://b/c?d=e#f=g && a://b/c?d]" & @CRLF & _ "hi. chrome-extension://flags hi. " & @CRLF & _ "hi. ms-help://good-luck/index.html hi. " & @CRLF & _ "hi. .iris.beep://really/dots. hi. " & @CRLF & _ "hi. iris.beep://really/dots?test=qs hi. " & @CRLF & _ "---" & @CRLF & _ "a://b]/c - Should match `a://b` - it's smallest match." & @CRLF & _ "http://www.c:ool.com.au - this one's tricky, should match auth URIs: proto://user:pass@host. Including cases where the password could be omitted (`proto://user@host`.)" & @CRLF & _ "boop://really-/ -- technically domains shouldn't end in dashes or other 'special' chars, but this is technically a valid URI." & @CRLF & _ "---" & @CRLF & _ "a://b./c?d. -- bad dns, trailing dot: tricky w/o look-arounds. (Adding an OR pattern would muddle the returned data indexes.) -- should match `a://b`" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "Invalid Examples:" & @CRLF & _ "https://www...google...com" & @CRLF & _ "https://we@.com" & @CRLF & _ "https://asdas-.com" & @CRLF & _ "http://-apple-.com" & @CRLF & _ "a://(b/c" & @CRLF & _ "chrome-extension)://flags" & @CRLF & _ "ms-help://|good-luck.html" & @CRLF & _ ". , ; : ) ] } " & @CRLF & _ "" 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