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!#$%&'*+\/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?" & @CRLF & _ "" Local $sString = "frankp@gmail.com" & @CRLF & _ "shannon.eee@gmail.com" & @CRLF & _ "franks&shannon@gmail.com" & @CRLF & _ "frank%ddd@gmail.com" & @CRLF & _ "frank@gmail$.com" & @CRLF & _ "frank@gmail_gmail.com" & @CRLF & _ "frank@gmail.research.com" & @CRLF & _ "joe@ggg.gg.cccc.com" & @CRLF & _ "joe..joe@gmail.com" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "/" & @CRLF & _ "https://stackoverflow.com/questions/5174171/fix-regular-expression-for-emails-to-not-allow-consecutive-periods/5174201#5174201" & @CRLF & _ "" & @CRLF & _ "*To avoid matching two consecutive dots you can add a negative lookahead at the beginning of your regular expression:" & @CRLF & _ "" & @CRLF & _ "/^(?!.*\.{2})[a-z0-9etc..." & @CRLF & _ " ------------" & @CRLF & _ "It will fail to match if there are two consecutive periods anywhere in the string and it doesn't require any other modifications to your original regular expression." & @CRLF & _ "" & @CRLF & _ "However it seems a bad idea as your regular expression isn't correct in the first place. If you insist on using regular expressions to validate email addresses, try this:" & @CRLF & _ "*/" & @CRLF & _ "" & @CRLF & _ "wilson..gmail.com" & @CRLF & _ "wilson.gmail.com" & @CRLF & _ "^(?!.*\.{2})/[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?" & @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