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)^[^.#,]*[.#,].*?\bMY_STRING\b[^,\r\n]*;(?:video|comment)(*SKIP)(*FAIL)|\bMY_STRING\b" Local $sString = "[1]" & @CRLF & _ "text,MY_STRING ;comment " & @CRLF & _ "text,MY_STRING text ;comment " & @CRLF & _ "text,text MY_STRING text ;comment " & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "-> dont catch any above because exist a" & @CRLF & _ "**comma** before #MY_STRING# and ;comment after." & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[2]" & @CRLF & _ "text, MY_STRING , text ;comment " & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "-> catch because exist a **comma** after #MY_STRING#" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[3]" & @CRLF & _ "text, MY_STRING, MY_STRING ;comment" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "-> catch first #MY_STRING# but don't catch last #MY_STRING#" & @CRLF & _ "because she is between , and ;comment" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[4]" & @CRLF & _ "MY_STRING" & @CRLF & _ "MY_STRING,text" & @CRLF & _ "text, MY_STRING," & @CRLF & _ "MY_STRING ;comment " & @CRLF & _ "text MY_STRING ;comment " & @CRLF & _ "text,MY_STRING,text ;comment" & @CRLF & _ "%MY_STRING% , (MY_STRING)" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "-> catch all, because there's no [comma . #] preceding #MY_STRING#" & @CRLF & _ "and no [# ;comment ;video] succeeding" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[5]" & @CRLF & _ ".MY_STRING" & @CRLF & _ "#MY_STRING" & @CRLF & _ "MY_STRING#" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "- > dont catch any" & @CRLF & _ "Independent of where MY_STRING is, either what it has between, don't catch any, because they have . or # preceding/proceeding the string." & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[6]" & @CRLF & _ "MY_STRING, .MY_STRING, #MY_STRING, text, MY_STRING" & @CRLF & _ "text, MY_STRING#, MY_STRING, .MY_STRING" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "-> same as above, just catch MY_STRING samples not containing . #" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[7]" & @CRLF & _ "text, MY_STRING ;video" & @CRLF & _ "MY_STRING ;video" & @CRLF & _ "#MY_STRING, MY_STRING, text, text MY_STRING ;video" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "- > In this case, the string will not be caught independent of where it is or what it has preceding/succeeding because exist the string ;video at the ending." & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[8]" & @CRLF & _ "text,MY_STRING, text ;comment" & @CRLF & _ " ^ ok catch (reason explained above)" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[9]" & @CRLF & _ "text,MY_STRING@ text ;comment" & @CRLF & _ "-------------------------------------------------------------- ^ dont catch, because there's no comma after the string, and there's a comma before and ;comment after" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[10]" & @CRLF & _ "MY_STRING,text,#MY_STRING,text,text,%MY_STRING% @ $text #text <text> ;comment" & @CRLF & _ "^[1] ^[2] ^[3]" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "[1] catch" & @CRLF & _ "[2] don't (# preceding)" & @CRLF & _ "[3] don't catch, because there's a comma preceding, no comma succeding and at the end line exist the string ;comment" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "[11]" & @CRLF & _ ".MY_STRING,text,MY_STRING,text,text,%MY_STRING% @ $text, #text <text> ;comment" & @CRLF & _ "^[1] ^[2] ^[3] ^[4]" & @CRLF & _ "--------------------------------------------------------------" & @CRLF & _ "[1] don't (dot preceding)" & @CRLF & _ "[2] catch" & @CRLF & _ "[3] catch because there's a comma on [4] so the string is not anymore between a comma preceding and ;comment succeeding, she is now between a comma preceding a comma succeeding and ;comment" 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