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

/
/
gx

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 = "(?x) (?(DEFINE)" & @CRLF & _ " (?<addr_spec> (?&local_part) @ (?&domain) )" & @CRLF & _ " (?<local_part> (?&dot_atom) | (?&quoted_string) | (?&obs_local_part) )" & @CRLF & _ " (?<domain> (?&dot_atom) | (?&domain_literal) | (?&obs_domain) )" & @CRLF & _ " (?<domain_literal> (?&CFWS)? \[ (?: (?&FWS)? (?&dtext) )* (?&FWS)? \] (?&CFWS)? )" & @CRLF & _ " (?<dtext> [\x21-\x5a] | [\x5e-\x7e] | (?&obs_dtext) )" & @CRLF & _ " (?<quoted_pair> \\ (?: (?&VCHAR) | (?&WSP) ) | (?&obs_qp) )" & @CRLF & _ " (?<dot_atom> (?&CFWS)? (?&dot_atom_text) (?&CFWS)? )" & @CRLF & _ " (?<dot_atom_text> (?&atext) (?: \. (?&atext) )* )" & @CRLF & _ " (?<atext> [a-zA-Z0-9!#$%&'*+\/=?^_`{|}~-]+ )" & @CRLF & _ " (?<atom> (?&CFWS)? (?&atext) (?&CFWS)? )" & @CRLF & _ " (?<word> (?&atom) | (?&quoted_string) )" & @CRLF & _ " (?<quoted_string> (?&CFWS)? " (?: (?&FWS)? (?&qcontent) )* (?&FWS)? " (?&CFWS)? )" & @CRLF & _ " (?<qcontent> (?&qtext) | (?&quoted_pair) )" & @CRLF & _ " (?<qtext> \x21 | [\x23-\x5b] | [\x5d-\x7e] | (?&obs_qtext) )" & @CRLF & _ "" & @CRLF & _ " # comments and whitespace" & @CRLF & _ " (?<FWS> (?: (?&WSP)* \r\n )? (?&WSP)+ | (?&obs_FWS) )" & @CRLF & _ " (?<CFWS> (?: (?&FWS)? (?&comment) )+ (?&FWS)? | (?&FWS) )" & @CRLF & _ " (?<comment> \( (?: (?&FWS)? (?&ccontent) )* (?&FWS)? \) )" & @CRLF & _ " (?<ccontent> (?&ctext) | (?&quoted_pair) | (?&comment) )" & @CRLF & _ " (?<ctext> [\x21-\x27] | [\x2a-\x5b] | [\x5d-\x7e] | (?&obs_ctext) )" & @CRLF & _ "" & @CRLF & _ " # obsolete tokens" & @CRLF & _ " (?<obs_domain> (?&atom) (?: \. (?&atom) )* )" & @CRLF & _ " (?<obs_local_part> (?&word) (?: \. (?&word) )* )" & @CRLF & _ " (?<obs_dtext> (?&obs_NO_WS_CTL) | (?&quoted_pair) )" & @CRLF & _ " (?<obs_qp> \\ (?: \x00 | (?&obs_NO_WS_CTL) | \n | \r ) )" & @CRLF & _ " (?<obs_FWS> (?&WSP)+ (?: \r\n (?&WSP)+ )* )" & @CRLF & _ " (?<obs_ctext> (?&obs_NO_WS_CTL) )" & @CRLF & _ " (?<obs_qtext> (?&obs_NO_WS_CTL) )" & @CRLF & _ " (?<obs_NO_WS_CTL> [\x01-\x08] | \x0b | \x0c | [\x0e-\x1f] | \x7f )" & @CRLF & _ "" & @CRLF & _ " # character class definitions" & @CRLF & _ " (?<VCHAR> [\x21-\x7E] )" & @CRLF & _ " (?<WSP> [ \t] )" & @CRLF & _ " )" & @CRLF & _ " ^(?&addr_spec)$" Local $sString = "fdas@gad.com" 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