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

/
/
Uig

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation // 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 = #"<a(.*?)><img(.*?)(\/)?><\/a>"# let regex = try! NSRegularExpression(pattern: pattern, options: .caseInsensitive) let testString = #""" <h4>Bild mit Verlinkung und ohne Caption</h4> <p><a title="" data-original-title="" href="/site/assets/files/1807/bora_bora_3.jpg"><img alt="Rochen" class="align_left" src="/site/assets/files/1807/bora_bora_3.150x0-is.jpg" width="150"></a>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</p> <h4>Bild mit Verlinkung und mit Caption</h4> <figure class="align_left"><a title="" data-original-title="" href="/site/assets/files/1807/bora_bora_3.jpg"><img alt="Rochen" src="/site/assets/files/1807/bora_bora_3.132x0-is.jpg" width="132"></a> <figcaption>Rochen</figcaption></figure><p>Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.</p> """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #"<a$1 class="thumbnail"><div class="scalecontainer"><span class="roll"></span><img$1></div></a>"# let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString) 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