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

/
/
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 $sRegex = "(?m)^(?!-00:00)(?=^(?:Z|[\+\-](?:0[0-9]|1[012]):00|\+0[34569]:30|\+10:30|-03:30|-09:30|\+13:00|\+14:00|\+05:45|\+08:45|\+12:45))^((Z)|([\+\-])(\d\d):(\d\d))$" Local $sString = "// Time Zone UTC Offsets in actual use for ISO 8601 / RFC 3339 (Museum of Bad Data)" & @CRLF & _ "" & @CRLF & _ "// Accept: UTC indicator" & @CRLF & _ "Z" & @CRLF & _ "// Accept: Valid +xx:00" & @CRLF & _ "+00:00" & @CRLF & _ "+01:00" & @CRLF & _ "+02:00" & @CRLF & _ "+03:00" & @CRLF & _ "+04:00" & @CRLF & _ "+05:00" & @CRLF & _ "+06:00" & @CRLF & _ "+07:00" & @CRLF & _ "+08:00" & @CRLF & _ "+09:00" & @CRLF & _ "+10:00" & @CRLF & _ "+11:00" & @CRLF & _ "+12:00" & @CRLF & _ "+13:00" & @CRLF & _ "+14:00" & @CRLF & _ "// Accept: Valid -xx:00" & @CRLF & _ "-01:00" & @CRLF & _ "-02:00" & @CRLF & _ "-03:00" & @CRLF & _ "-04:00" & @CRLF & _ "-05:00" & @CRLF & _ "-06:00" & @CRLF & _ "-07:00" & @CRLF & _ "-08:00" & @CRLF & _ "-09:00" & @CRLF & _ "-10:00" & @CRLF & _ "-11:00" & @CRLF & _ "-12:00" & @CRLF & _ "" & @CRLF & _ "// Accept: Valid +xx:30" & @CRLF & _ "+03:30" & @CRLF & _ "+04:30" & @CRLF & _ "+05:30" & @CRLF & _ "+06:30" & @CRLF & _ "+09:30" & @CRLF & _ "+10:30" & @CRLF & _ "" & @CRLF & _ "// Accept: Valid +xx:45" & @CRLF & _ "+05:45" & @CRLF & _ "+08:45" & @CRLF & _ "+12:45" & @CRLF & _ "" & @CRLF & _ "// Accept: Valid -xx:30" & @CRLF & _ "-03:30" & @CRLF & _ "-09:30" & @CRLF & _ "" & @CRLF & _ "// Accept: Valid: 30 offsets" & @CRLF & _ "" & @CRLF & _ "+03:30" & @CRLF & _ "+04:30" & @CRLF & _ "+05:30" & @CRLF & _ "+06:30" & @CRLF & _ "+09:30" & @CRLF & _ "+10:30" & @CRLF & _ "-03:30" & @CRLF & _ "-09:30" & @CRLF & _ "" & @CRLF & _ "// Accept: Valid :45 offsets" & @CRLF & _ "+05:45" & @CRLF & _ "+08:45" & @CRLF & _ "+12:45" & @CRLF & _ "" & @CRLF & _ "// Reject: valid RFC 3339, invalid ISO 8601" & @CRLF & _ "" & @CRLF & _ "-00:00" & @CRLF & _ "" & @CRLF & _ "// Reject: no such UTC offset in use" & @CRLF & _ "-13:00" & @CRLF & _ "-14:00" & @CRLF & _ "+00:01" & @CRLF & _ "+00:03" & @CRLF & _ "+00:99" & @CRLF & _ "+20:00" & @CRLF & _ "+0:00" & @CRLF & _ "// Reject: no such UTC offset in use" & @CRLF & _ "" & @CRLF & _ "+01:30" & @CRLF & _ "+07:30" & @CRLF & _ "+08:30" & @CRLF & _ "+02:30" & @CRLF & _ "+11:30" & @CRLF & _ "+12:30" & @CRLF & _ "+13:30" & @CRLF & _ "+14:30" & @CRLF & _ "-01:30" & @CRLF & _ "-02:30" & @CRLF & _ "-04:30" & @CRLF & _ "-05:30" & @CRLF & _ "-06:30" & @CRLF & _ "-07:30" & @CRLF & _ "-08:30" & @CRLF & _ "-10:30" & @CRLF & _ "-11:30" & @CRLF & _ "-12:30" & @CRLF & _ "-13:30" & @CRLF & _ "-14:30" & @CRLF & _ "" & @CRLF & _ "// Reject: Unused :45 offsets" & @CRLF & _ "+01:45" & @CRLF & _ "+02:45" & @CRLF & _ "+03:45" & @CRLF & _ "+04:45" & @CRLF & _ "+06:45" & @CRLF & _ "+07:45" & @CRLF & _ "+09:45" & @CRLF & _ "+10:45" & @CRLF & _ "+11:45" & @CRLF & _ "+13:45" & @CRLF & _ "+14:45" & @CRLF & _ "-01:45" & @CRLF & _ "-02:45" & @CRLF & _ "-03:45" & @CRLF & _ "-04:45" & @CRLF & _ "-05:45" & @CRLF & _ "-06:45" & @CRLF & _ "-07:45" & @CRLF & _ "-08:45" & @CRLF & _ "-09:45" & @CRLF & _ "-10:45" & @CRLF & _ "-11:45" & @CRLF & _ "-12:45" & @CRLF & _ "-13:45" & @CRLF & _ "-14:45" & @CRLF & _ "" & @CRLF & _ "+01:15" & @CRLF & _ "+02:15" & @CRLF & _ "+03:15" & @CRLF & _ "+04:15" & @CRLF & _ "+05:15" & @CRLF & _ "+06:15" & @CRLF & _ "+07:15" & @CRLF & _ "+08:15" & @CRLF & _ "+09:15" & @CRLF & _ "+10:15" & @CRLF & _ "+11:15" & @CRLF & _ "+12:15" & @CRLF & _ "+13:15" & @CRLF & _ "+14:15" & @CRLF & _ "-01:15" & @CRLF & _ "-02:15" & @CRLF & _ "-03:15" & @CRLF & _ "-04:15" & @CRLF & _ "-05:15" & @CRLF & _ "-06:15" & @CRLF & _ "-07:15" & @CRLF & _ "-08:15" & @CRLF & _ "-09:15" & @CRLF & _ "-10:15" & @CRLF & _ "-11:15" & @CRLF & _ "-12:15" & @CRLF & _ "-13:15" & @CRLF & _ "-14:15" & @CRLF & _ "" & @CRLF & _ "// Reject: Z stands alone" & @CRLF & _ "Z00:00" & @CRLF & _ "Z00" & @CRLF & _ "Z0" & @CRLF & _ "// Reject: hyphen required" & @CRLF & _ "0100" & @CRLF & _ "+0100" & @CRLF & _ "-0100" & @CRLF & _ "// Reject: colon required" & @CRLF & _ "+0100" & @CRLF & _ "// Reject: No extra characters" & @CRLF & _ "2001-02-03T04:05:06.007+0800" & @CRLF & _ "+08:00 " & @CRLF & _ " +08:00" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "### Expanded Pattern:" & @CRLF & _ "" & @CRLF & _ "```" & @CRLF & _ "^(?!-00:00)(?=^(?:Z|[\+\-](?:0[0-9]|1[012]):00|\+0[34569]:30|\+10:30|-03:30|-09:30|\+13:00|\+14:00|\+05:45|\+08:45|\+12:45))^((Z)|([\+\-])(\d\d):(\d\d))$" & @CRLF & _ "```" & @CRLF & _ "" & @CRLF & _ "```" & @CRLF & _ "^ # use zero-width assertions to capture all the special cases:" & @CRLF & _ "(?!-00:00) # not -00:00" & @CRLF & _ "(?=^(?:" & @CRLF & _ " Z # Z alone works," & @CRLF & _ " |[\+\-](?:0[0-9]|1[012]):00 # and all other +/- xx:00s," & @CRLF & _ " |\+0[34569]:30|\+10:30|-03:30|-09:30 # the +/- xx:30s." & @CRLF & _ " |\+13:00|\+14:00|\+05:45|\+08:45|\+12:45 # and these special cases" & @CRLF & _ ")) # Now that we've forced only positive matches, let's capture the pieces:" & @CRLF & _ "^( # G1: the whole offset" & @CRLF & _ " (Z) | # G2: UTC indicator or nil" & @CRLF & _ " ([\+\-]) # G3: +/- direction" & @CRLF & _ " (\d\d) # G4: "hours" part of offset" & @CRLF & _ " :" & @CRLF & _ " (\d\d) # G5: "minutes" part of offset" & @CRLF & _ ")$" & @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