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

/
/
g

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(([A-Za-z_-]*)="(.*?)")"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" <DT><A HREF="http://www.tripadvisor.fr/ShowUserReviews-g187849-d646539-r137197174-Hotel_Paradiso-Milan_Lombardy.html" ADD_DATE="1441047526" LAST_MODIFIED="1441047526" ICON_URI="http://static.tacdn.com/favicon.ico" ICON="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAABE0lEQVQ4jd2QMWrDMBiF36xCblDRniFbyeADVMRDQ3qA9gyeHLp56FI6FEoIZHDJZIM7GfEfoz6A1+4atOR1kY1jXOhY8sNb9Ok9Pf3Af54ZgKug2V9NcwA7AC0AjtQGNh+bXgGkAJ4BHAEwSwzZvpwoS0wXdAx30+BFNPHaScjAPFbUtVhrrSkidM6xrmtqrZklhlliOMUA3A+/8SUilKLkbmkoRUkR6SuLCPNiz9unG+bFvmPNMMA757iNY9aXF9zGMb33BOA7ZjYLXr+BZrMYsn4aay2l+uT76o5SVcMGtNbyUH5wmUY8lPlkg34H3nuKCJVSfYBS6oRN7QDhoAnVGgAPAL6DHkdsPTb/Nqugc54f+w3c0e+99WoAAAAASUVORK5CYII=">Je donnerais un zéro si je pouvais - Avis de voyageurs sur Hotel Paradiso, Milan - TripAdvisor</A> """# 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