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

/
/

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"^\s*(?:<\?xml[^>]+>)?\s*<([^>]+?)>[\s\S]+?<\/\1>\s*?$"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" <?xml version="1.0" encoding="UTF-8"?> <Recordings> <Recording OVSTag="R00259003F89415063015030509" Name="test"> <Channel EndTC="15:03:59:10" BeginTC="15:03:05:22" Index="3"/> <Clip UName="801" OVSTag="C00259003F89415063015394226" Name="test_sub_1"> <Channel OutPoint="15:03:20:19" InPoint="15:03:05:22" Default="true" Index="3"/> <SmartEvent ID="b703578e-8dd1-6b72-c8c7-237132f66652"/> <SmartEvent ID="9287112f-45a6-1f43-0c28-76111b1b710f"/> <SmartEvent ID="a71c9fff-d1ae-7f89-5f1a-7a0a281f9904"/> </Clip> </Recording> </Recordings> <SmartEvents> <SmartEvent PageID="f3e9e264-3f1a-0f15-814a-cc7c535c1251" ID="b703578e-8dd1-6b72-c8c7-237132f66652" Name="FOUL"/> <SmartEvent PageID="bc3e8a3b-ea74-dad2-bd55-49a7d9725b83" ID="9287112f-45a6-1f43-0c28-76111b1b710f" Name="MESSI"/> <SmartEvent PageID="d15ed885-b68b-69db-8d76-3dc21e47d1d1" ID="a71c9fff-d1ae-7f89-5f1a-7a0a281f9904" Name="RAMOS"/> </SmartEvents> <SmartEventPages> <SmartEventPage ID="d15ed885-b68b-69db-8d76-3dc21e47d1d1" Name="Real Team"/> <SmartEventPage ID="f3e9e264-3f1a-0f15-814a-cc7c535c1251" Name="Action"/> <SmartEventPage ID="bc3e8a3b-ea74-dad2-bd55-49a7d9725b83" Name="Barcelona Team"/> </SmartEventPages> """# let stringRange = NSRange(location: 0, length: testString.utf16.count) if let firstMatch = regex.firstMatch(in: testString, range: stringRange) { let result: [String] = (1 ..< firstMatch.numberOfRanges).map { (testString as NSString).substring(with: firstMatch.range(at: $0)) } print(result) } else { print("No matches were found.") }

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