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

Generated Code

import Foundation let pattern = #"https://www\.roco\.cc/rde/(produkte/([A-z]*)|home-neuheiten)/([A-z]*)/*([0-9]{5,})-([A-z]*)-(?P<baureihe>el|e|cc|litra-eb|s|br|tkt|rh)*(?P<number>[e%0-9\-]*)-([a-z\-]*).html"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" https://www.roco.cc/rde/produkte/lokomotiven/dampflokomotiven/52208-dampflokomotive-br-80-db.html https://www.roco.cc/rde/produkte/lokomotiven/dampflokomotiven/36086-dampflokomotive-44-0104-8-dr.html https://www.roco.cc/rde/produkte/lokomotiven/dampflokomotiven/70038-dampflokomotive-56-2009-1-dr.html https://www.roco.cc/rde/produkte/lokomotiven/dampflokomotiven/70040-dampflokomotive-231-e-34-sncf.html https://www.roco.cc/rde/produkte/lokomotiven/dampflokomotiven/7110002-dampflokomotive-tkt-21-pkp.html https://www.roco.cc/rde/produkte/lokomotiven/dampflokomotiven/70047-dampflokomotive-521591-obb.html https://www.roco.cc/rde/produkte/lokomotiven/dampflokomotiven/70046-dampflokomotive-br-8970%e2%80%9375-dr.html https://www.roco.cc/rde/produkte/lokomotiven/dampflokomotiven/73030-dampflokomotive-rh-86-obb.html https://www.roco.cc/rde/produkte/lokomotiven/elektrolokomotiven/60226-elektrolokomotive-rh-372-cd-cargo.html https://www.roco.cc/rde/produkte/lokomotiven/elektrolokomotiven/60239-elektrolokomotive-s-4992002-csd.html https://www.roco.cc/rde/produkte/lokomotiven/elektrolokomotiven/60974-elektrolokomotive-193-759-8-ns.html https://www.roco.cc/rde/produkte/lokomotiven/elektrolokomotiven/60492-elektrolokomotive-1116-182-7-bundesheer-obb.html https://www.roco.cc/rde/produkte/lokomotiven/elektrolokomotiven/60921-elektrolokomotive-litra-eb-3202-dsb.html https://www.roco.cc/rde/produkte/lokomotiven/elektrolokomotiven/70618-elektrolokomotive-cc-6574-sncf.html https://www.roco.cc/rde/produkte/lokomotiven/elektrolokomotiven/70653-elektrolokomotive-e-186-012-ns.html https://www.roco.cc/rde/home-neuheiten/70673-elektrolokomotive-el-18-2260-go-ahead.html """# 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