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

/
/
gmx

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 = "(?mx)^#start of line" & @CRLF & _ "(?![^\n!]*!{2,})" & @CRLF & _ "(?=[^_\n]*_[^_]*) #if _ exists, then:" & @CRLF & _ "([^_:]+) #mandatory group 1" & @CRLF & _ "((?=:[^:\n]):[^:_(\n]+|) #optional group 2" & @CRLF & _ "(_(?!_)) #group 3 mandatory" & @CRLF & _ "([^_\-(\n]+) # group 4 mandatory" & @CRLF & _ "\( #mandatory (" & @CRLF & _ "([^()\n]+) # group 5 mandatory" & @CRLF & _ "\) #mandatory )" & @CRLF & _ "((?=!)!|) # group 6 optional" & @CRLF & _ "((?=:[^!:@\n]):[^!:@\n]+|) # group 7 optional" & @CRLF & _ "((?=::[^!:@\n])::[^!:@\n]+|) #group 8 optional" & @CRLF & _ "((?=@[^!:@\n])@[^!:@\n]+|) #group 9 optional" & @CRLF & _ "$ #end of line" Local $sString = "# OK - Matches all components if all are provided" & @CRLF & _ "contextClassName:pc_ruleName(param_One paramTwo)!:pc::pe@media" & @CRLF & _ "" & @CRLF & _ "# OK - Return group 2 blank when no : exists before _ which is group 3" & @CRLF & _ "contextClassName_ruleName(param_One paramTwo)!:pc::pe@media" & @CRLF & _ "" & @CRLF & _ "# OK - When ! is not provided return group 6 blank" & @CRLF & _ "contextClassName_ruleName(param_One paramTwo):pc::pe@media" & @CRLF & _ "" & @CRLF & _ "# NOTOK - More than one consecutive !" & @CRLF & _ "contextClassName_ruleName(param_One paramTwo)!!:pc::pe@media" & @CRLF & _ "" & @CRLF & _ "# NOTOK - 3 More than two : at instruction tail" & @CRLF & _ "contextClassName_ruleName(param_One paramTwo):::pe@media" & @CRLF & _ "" & @CRLF & _ "# OK - 2 At instruction tail :: is resolved to group 8 " & @CRLF & _ "contextClassName_ruleName(param_One paramTwo)::pe@media" & @CRLF & _ "" & @CRLF & _ "# OK - 1 At instruction tail : is resolved to group 7 " & @CRLF & _ "contextClassName_ruleName(param_One paramTwo):pe@media" & @CRLF & _ "" & @CRLF & _ "# OK - At instruction start : followed by chars" & @CRLF & _ "contextClassName:pc_ruleName(param_One paramTwo):pe@media" & @CRLF & _ "" & @CRLF & _ "# NOTOK - At instruction start : not followed by chars" & @CRLF & _ "contextClassName:_ruleName(param_One paramTwo):pe@media" & @CRLF & _ "" & @CRLF & _ "# NOTOK - At instruction start :: followed by chars" & @CRLF & _ "contextClassName::pc_ruleName(param_One paramTwo):pe@media" & @CRLF & _ "" & @CRLF & _ "# OK - Whole instruction tail is optional " & @CRLF & _ "contextClassName:pc_ruleName(param_One paramTwo)" & @CRLF & _ "" & @CRLF & _ "# OK - Parameter value can contain anything" & @CRLF & _ "contextClassName:pc_ruleName(param_One param#$^Two)" 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