Regular Expressions 101

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  • Unit Tests (12)

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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

Language

Generated Code

import Foundation let pattern = #"(?<!SQ\d{0}|\d|\d{2})(51\d{14}|52\d{14}|53\d{14}|54\d{14}|55\d{14}|36\d{12}|34\d{13}|37\d{13}|4\d{15}|4\d{12}|\d{4}(-|\s)\d{4}(-|\s)\d{4}(-|\s)\d{4}|\d{3}(-|\s)\d{3}(-|\s)\d{3}(-|\s)\d{3}(-|\s)\d{3}|\d{4}(-|\s)\d{6}(-\s)\d{5}|6\d{15})"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = ##""" <Payment> <PCard expiration="2061-04-00" name="Grainger AB" number="41111111111111114222222222222"/> </Payment> <PCard expiration="2022-04" number="4005-5511-2233-4450"/> <Payment> Space <PCard expiration="2022-04" number="4005 5511 2233 4450"/> Tab space <PCard expiration="2022-04" number="4005 551122334450"/> <PCard expiration="2022-04" number="4005 5511 2233 4450"/> new line <PCard expiration="2022-04" number="4005400540054005"/> <PCard expiration="2022-04" number="4005 5511 2233 4450"/> carriage return <PCard expiration="2022-04" number="4005 5511 2233 4450"/> </Payment> combination of <Payment> <PCard expiration="2022-04" number="4005- 5511 -2233-4450"/> </Payment> <PCard expiration="2061-04-00" name="Grainger AB" number="4255726800010"/> <PCard expiration="2061-04-00" name="Grainger AB" number="@#@@@$@4255726800010"/> <PCard expiration="2061-04-00" name="Grainger AB" number="SQ#4255726800010"/> <PCard expiration="2061-04-00" name="Grainger AB" number="45a$4255726800010"/> <PCard expiration="2061-04-00" name="Grainger AB" number="12SQ%4255726800010"/> <PCard expiration="2061-04-00" name="Grainger AB" number="4255726800010@121212"/> <PCard expiration="2061-04-00" name="Grainger AB" number="4255726800010#SQ"/> <PCard expiration="2061-04-00" name="Grainger AB" number="4255726800010$a54"/> <PCard expiration="2061-04-00" name="Grainger AB" number="4255726800010%SQ12"/> <SupplierPartID>4222222222222</SupplierPartID> <SupplierPartID> 4222222222222</SupplierPartID> <SupplierPartID>SQ4222222222222</SupplierPartID> <SupplierPartID>SQ134222222222222</SupplierPartID> <SupplierPartAuxiliaryID>WWGSQ134256726800010</SupplierPartAuxiliaryID> """## let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } print(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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression