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

/
/
uiU

Test String

Code Generator

Language

Generated Code

import Foundation // WARNING: You included a flag that Swift doesn't support: u // When this flag is set, it makes the pattern and subject strings to be treated as unicode. // Swift already treats the pattern and subject strings as unicode by default, so including this flag is redundant. // WARNING: You included a flag that Swift doesn't support: U // When this flag is set, it inverts the "greediness" of the quantifiers so that they are not greedy by default, but become greedy if followed by '?'. // As an alternative, this effect can also be achieved by setting a (?U) modifier setting within the pattern or by a question mark behind a quantifier (e.g. .*?). let pattern = #"\<[\s]*h5+[\s]*\>(.*)\<[\s]*\/h5+[\s]*\>"# let regex = try! NSRegularExpression(pattern: pattern, options: .caseInsensitive) let testString = #""" asdasd asdfsf <meta name="description" itemprop="description" content="Über die SEO Software und Toolbox analysieren Sie Ihre Domain sowie der Mitbewerber. Die Tools zu Ranking-Daten, Keywords, Onpage, Backlinks, Social decken alle Bereiche des Online Marketings ab. "/> afasdfs asdfdf<h5>Webinare &amp; Präsenzschulungen für Ihren Erfolg!</h5> /\<[\s]*'.$tag.'+[\s]*\>(.*)\<[\s]*\/'.$tag.'+[\s]*\>/u """# 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