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

/
/
igm

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"^((AT)(U\d{8})|(BE)(0\d{9})|(BG)(\d{9,10})|(CY)(\d{8}[LX])|(CZ)(\d{8,10})|(DE)(\d{9})|(DK)(\d{8})|(EE)(\d{9})|(EL|GR)(\d{9})|(ES)([\dA-Z]\d{7}[\dA-Z])|(FI)(\d{8})|(FR)([\dA-Z]{2}\d{9})|(HU)(\d{8})|(IE)(\d{7}[A-Z]{2})|(IT)(\d{11})|(LT)(\d{9}|\d{12})|(LU)(\d{8})|(LV)(\d{11})|(MT)(\d{8})|(NL)(\d{9}(B\d{2}|BO2))|(PL)(\d{10})|(PT)(\d{9})|(RO)(\d{2,10})|(SE)(\d{12})|(SI)(\d{8})|(SK)(\d{10}))$"# let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .caseInsensitive]) let testString = #""" ATU12345678 BE0123456789 BG123456789 BG1234567890 CY12345678X CY12345678L CZ12345678 CZ123456789 CZ1234567890 DE123456789 DK12345678 EE123456789 EL123456789 GR123456789 ESX12345678 ES12345678X ESX1234567X FI12345678 FR12345678901 FRX1234567890 FR1X123456789 FRXX123456789 HU12345678 IE1234567WA IE1234567FA IT12345678901 LT123456789 LT123456789012 LU12345678 LV12345678901 MT12345678 NL123456789B01 NL123456789BO2 PL1234567890 PT123456789 RO1234567890 SE123456789012 SK1234567890 """# 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