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

r"
"
g

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"background-image: url\(\"\/\/external-content\.duckduckgo\.com\/iu\/\?u=(.*)&f=1&h=110\"\);"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" background-image: url("//external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fimage.cnbcfm.com%2Fapi%2Fv1%2Fimage%2F106261274-1574442599483rtx7a0ls.jpg%3Fv%3D1574452686&f=1&h=110"); background-image: url("//external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fimg-s-msn-com.akamaized.net%2Ftenant%2Famp%2Fentityid%2FAAMcjDx.img%3Fh%3D630%26w%3D1200%26m%3D6%26q%3D60%26o%3Dt%26l%3Df%26f%3Djpg%26x%3D2091%26y%3D602&f=1&h=110"); background-image: url("//external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fs.yimg.com%2Fny%2Fapi%2Fres%2F1.2%2FJSwEklq4.Wb9rSN4Jos8Pw--%2FYXBwaWQ9aGlnaGxhbmRlcjt3PTIwMDA7aD0xNTAw%2Fhttps%3A%2F%2Fs.yimg.com%2Fuu%2Fapi%2Fres%2F1.2%2FqLOFL2gnGPZmvsHf_FnjvQ--~B%2FaD0yMzIxO3c9MzA5NTthcHBpZD15dGFjaHlvbg--%2Fhttps%3A%2F%2Fmedia.zenfs.com%2Fen%2Fbusiness_insider_articles_888%2F9d51192cb64af28f340c46700be07207&f=1&h=110"); background-image: url("//external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fi.insider.com%2F601816796dfbe10018e0106a%3Fwidth%3D1200%26format%3Djpeg&f=1&h=110"); background-image: url("//external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fa57.foxnews.com%2Fstatic.foxbusiness.com%2Ffoxbusiness.com%2Fcontent%2Fuploads%2F2019%2F11%2F0%2F0%2FAP19326175844301-e1574611302337.jpg%3Fve%3D1%26tl%3D1&f=1&h=110"); """# 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