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)\b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b34[0-9]{13}\b|\b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b37[0-9]{13}\b" Local $sString = "American Express" & @CRLF & _ "Requirements: American Express cards start with the number 34 or 37 and have 15 digits. Pattern is 4-6-5 when having spaces or dashes." & @CRLF & _ "" & @CRLF & _ "Pattern Parts:" & @CRLF & _ "Starts with number 34 and 15 length:" & @CRLF & _ "1) \b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b34[0-9]{13}\b " & @CRLF & _ "" & @CRLF & _ "Starts with number 37 and 15 length:" & @CRLF & _ "2) \b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b37[0-9]{13}\b" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "Combining 1-2 to form one pattern:" & @CRLF & _ "\b(34[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b34[0-9]{13}\b|\b(37[0-9]{2}[ -])([0-9]{6}[ -])[0-9]{5}\b|\b37[0-9]{13}\b" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "Test Cases:" & @CRLF & _ "Positive (Should fire):" & @CRLF & _ "15 length, no space, start with 34 342312341234112" & @CRLF & _ "15 length, dashes, start with 34 3423-123456-12345" & @CRLF & _ "15 length, spaces, start with 34 3423 123456 12345" & @CRLF & _ "" & @CRLF & _ "15 length, no space, start with 37 372112341234123" & @CRLF & _ "15 length, dashes, start with 37 3721-123456-12345" & @CRLF & _ "15 length, spaces, start with 37 3721 123456 12345" & @CRLF & _ "" & @CRLF & _ "Embedded in sentence with space:" & @CRLF & _ "15 length, no space, start with 34 Here is the cc: 342312341234112" & @CRLF & _ "15 length, dashes, start with 34 Here is the cc: 3423-123456-12345" & @CRLF & _ "15 length, spaces, start with 34 Here is the cc: 3423 123456 12345" & @CRLF & _ "" & @CRLF & _ "15 length, no space, start with 37 Here is the cc: 372112341234123" & @CRLF & _ "15 length, dashes, start with 37 Here is the cc: 3721-123456-12345" & @CRLF & _ "15 length, spaces, start with 37 Here is the cc: 3721 123456 12345" & @CRLF & _ "" & @CRLF & _ "15 length, no space, start with 34 Credit Card#:342312341234112" & @CRLF & _ "15 length, dashes, start with 34 Credit Card#:3423-123456-12345" & @CRLF & _ "15 length, spaces, start with 34 Credit Card#:3423 123456 12345" & @CRLF & _ "" & @CRLF & _ "15 length, no space, start with 37 Credit Card#:372112341234123" & @CRLF & _ "15 length, dashes, start with 37 Credit Card#:3721-123456-12345" & @CRLF & _ "15 length, spaces, start with 37 Credit Card#:3721 123456 12345" & @CRLF & _ "" & @CRLF & _ "Negative (Should Not Fire):" & @CRLF & _ "15 length, no space, not start with 34 352312341234112" & @CRLF & _ "15 length, dashes, not start with 34 3523-123456-12345" & @CRLF & _ "15 length, spaces, not start with 34 3523 123456 12345" & @CRLF & _ "" & @CRLF & _ "15 length, no space, not start with 37 362112341234123" & @CRLF & _ "15 length, dashes, not start with 37 3621-123456-12345" & @CRLF & _ "15 length, spaces, not start with 37 3621 123456 12345" & @CRLF & _ "" & @CRLF & _ "15 length, no space, start with 34, embedded Credit Card Number342312341234112" & @CRLF & _ "15 length, dashes, start with 34, malformed 3423-1234-1234-112" & @CRLF & _ "" & @CRLF & _ "15 length num matching pattern but embedded User ID: 000000342312341234112000000" 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