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

/
/
gm

Test String

Code Generator

Generated Code

import Foundation let pattern = #"Zwechfreibaum01"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" //++++++++++08++++++++++++++++++++ /+++++++++++ App.jsx ++++++++++++ import React from "react"; import PictureListAs05 from "./components/PictureListAs05.jsx"; import PictureListAs06 from "./components/PictureListAs06.jsx"; export default function App() { return ( <div> <h1>AS05 – Bilderliste</h1> <div style={{ display: "flex", gap: "2rem" }}> <PictureListAs05 grenze={80} farbe1="green" farbe2="red" /> <PictureListAs06 grenze={100} farbe1="blue" farbe2="orange" /> </div> </div> ); } //+++++++++++++ PictureList05.jsx +++++++++++++++++++++++++ import React from "react"; import ShowPictureList from "./ShowPictureList.jsx"; const BILDER = [ { url: "https://picsum.photos/seed/a/400", alt: "Wald", datum: "2025-02-01", zahl: 120 }, { url: "https://picsum.photos/seed/b/400", alt: "Gebirge", datum: "2025-02-02", zahl: 60 }, { url: "https://picsum.photos/seed/c/400", alt: "Meer", datum: "2025-02-03", zahl: 200 }, { url: "https://picsum.photos/seed/d/400", alt: "Stadt", datum: "2025-02-04", zahl: 75 }, { url: "https://picsum.photos/seed/e/400", alt: "Wüste", datum: "2025-02-05", zahl: 95 }, { url: "https://picsum.photos/seed/f/400", alt: "Wiese", datum: "2025-02-06", zahl: 50 }, ]; export default function PictureListAs05({ grenze, farbe1, farbe2 }) { const GRENZE = grenze; const FARBE1 = farbe1; const FARBE2 = farbe2; return ( <div> <ShowPictureList bilder={BILDER} grenze={GRENZE} farbe1={FARBE1} farbe2={FARBE2} /> </div> ); } //++++++++++++++ PictureList06.jsx+++++++++++++++++++++++ import React from "react"; import ShowPictureList from "./ShowPictureList.jsx"; const BILDER = [ { url: "https://placebear.com/400/400", alt: "Bär im Wald", datum: "2025-02-01", zahl: 120 }, { url: "https://placebear.com/401/400", alt: "Bär am Berg", datum: "2025-02-02", zahl: 60 }, { url: "https://placebear.com/402/400", alt: "Bär am See", datum: "2025-02-03", zahl: 200 }, { url: "https://placebear.com/403/400", alt: "Bär in der Stadt",datum: "2025-02-04", zahl: 75 }, { url: "https://placebear.com/404/400", alt: "Bär in der Wüste",datum: "2025-02-05", zahl: 95 }, { url: "https://placebear.com/405/400", alt: "Bär auf der Wiese",datum: "2025-02-06", zahl: 50 }, ]; export default function PictureListAs06({ grenze, farbe1, farbe2 }) { const GRENZE = grenze; const FARBE1 = farbe1; const FARBE2 = farbe2; return ( <div> <ShowPictureList bilder={BILDER} grenze={GRENZE} farbe1={FARBE1} farbe2={FARBE2} /> </div> ); } //+++++++++++++++++++ PictureList.jsx ++++++++++++++++++++ import React, { useState } from "react"; export default function ShowPictureList({ bilder, grenze, farbe1, farbe2 }) { const threshold = Number(grenze) || 0; const imageArrayIndex = useState(0); const currentIndex = imageArrayIndex[0]; const setCurrentIndex = imageArrayIndex[1]; const borderColor = bilder[currentIndex].zahl > threshold ? farbe1 : farbe2; const currentImage = bilder[currentIndex]; return ( <> <ul> return ( <li key={currentIndex}> <img src={currentImage.url} alt={currentImage.alt} width={currentImage.zahl} style={{ border: `4px solid ${borderColor}` }} /> <p>{currentImage.alt}</p> <small>{currentImage.datum}</small> </li> ); </ul> <button onClick={() => setCurrentIndex(currentIndex + 1)}> Nächstes Bild </button> <button onClick={() => setCurrentIndex(currentIndex - 1)}> Vorheriges Bild </button> </> ); } //++++++++++ main.jsx +++++++++++++++++++ import { StrictMode } from 'react' import { createRoot } from 'react-dom/client' import App from './App.jsx' createRoot(document.getElementById('root')).render( <StrictMode> <App /> </StrictMode>, ) """# 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