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

/
/
gm

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 = "(?m)(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z0-9][a-z0-9-]{0,61}[a-z0-9]" Local $sString = "Valid domain name matching." & @CRLF & _ "Vote for it: http://stackoverflow.com/a/30007882/697313" & @CRLF & _ "" & @CRLF & _ "Sample text for testing:" & @CRLF & _ "abcdefghijklmnopqrstuvwxyz.ABCDEFGHIJKLMNOPQRSTUVWXYZ" & @CRLF & _ "0123456789 +-.,!@#$%^&*();\\/|<>\"\'" & @CRLF & _ "12345 -98.7 3.141 .6180 9,000 +42" & @CRLF & _ "555.123.4567 +1-(800)-555-2468" & @CRLF & _ "foodemo.net" & @CRLF & _ "bar.ba.test.co.uk" & @CRLF & _ "www.demo.com" & @CRLF & _ "http://foo.co.uk/" & @CRLF & _ "http://regexr.com/foo.html?q=bar" & @CRLF & _ "g.com" & @CRLF & _ "g-.com" & @CRLF & _ "com.g" & @CRLF & _ "-g.com" & @CRLF & _ "xn--d1ai6ai.xn--p1ai" & @CRLF & _ "xn-fsqu00a.xn-0zwm56d" & @CRLF & _ "xn--stackoverflow.com" & @CRLF & _ "stackoverflow.xn--com" & @CRLF & _ "stackoverflow.co.uk" & @CRLF & _ "google.com.au" & @CRLF & _ "" & @CRLF & _ "-0-0o.com" & @CRLF & _ "0-0o_.com (underscore not allowed)" & @CRLF & _ "a.net" & @CRLF & _ "-a.dot" & @CRLF & _ "0-0o.com" & @CRLF & _ "0-oz.co.uk" & @CRLF & _ "0-tension.com.br" & @CRLF & _ "0-wh-ao14-0.com-com.net" & @CRLF & _ "a-1234567890-1234567890-1234567890-1234567890-1234567890-1234-z.eu.us" & @CRLF & _ "a-1234567890-1234567890-1234567890-1234567890-1234567890-12345-z.eu.us (too long)" & @CRLF & _ "" & @CRLF & _ "List of valid domain names:" & @CRLF & _ "www.google.com" & @CRLF & _ "google.com" & @CRLF & _ "mkyong123.com" & @CRLF & _ "mkyong-info.com" & @CRLF & _ "sub.mkyong.com" & @CRLF & _ "sub.mkyong-info.com" & @CRLF & _ "mkyong.com.au" & @CRLF & _ "g.co" & @CRLF & _ "mkyong.t.t.co" & @CRLF & _ "" & @CRLF & _ "List of invalid domain names, and why:" & @CRLF & _ "mkyong.t.t.c – Tld must between 2 and 6 long" & @CRLF & _ "mkyong,com – Comma is not allow" & @CRLF & _ "mkyong – No Tld" & @CRLF & _ "mkyong.123 , Tld not allow digit (can easily fix for this)" & @CRLF & _ ".com – Must start with [A-Za-z0-9]" & @CRLF & _ "mkyong.com/users – No Tld" & @CRLF & _ "-mkyong.com – Cannot begin with a hyphen -" & @CRLF & _ "mkyong-.com – Cannot end with a hyphen -" & @CRLF & _ "sub.-mkyong.com – Cannot begin with a hyphen -" & @CRLF & _ "sub.mkyong-.com – Cannot end with a hyphen -" & @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