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

@
@
gmis

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"<a[^>]*href="(?<url>[^"]*(?<=\?|&)o=(?<number>\d+)[^"]*)"[^>]*>\s*last"# let regex = try! NSRegularExpression(pattern: pattern, options: [.anchorsMatchLines, .caseInsensitive, .dotMatchesLineSeparators]) let testString = #""" <div class="listing_thumbs_resultcontainer"> <span class="FloatLeft nav-next-btn"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=1&amp;q=nike air&amp;th=1" title="Go to first page">« First</a> <span class="nav-next-btn nohistory marginLeft"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=18&amp;q=nike air&amp;th=1" title="Go to previous page"> ‹ Previous </a> </span> &nbsp; <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=1&amp;q=nike air&amp;th=1" title="Page 1 of 29">1</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=2&amp;q=nike air&amp;th=1" title="Page 2 of 29">2</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=3&amp;q=nike air&amp;th=1" title="Page 3 of 29">3</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=4&amp;q=nike air&amp;th=1" title="Page 4 of 29">4</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=5&amp;q=nike air&amp;th=1" title="Page 5 of 29">5</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=6&amp;q=nike air&amp;th=1" title="Page 6 of 29">6</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=7&amp;q=nike air&amp;th=1" title="Page 7 of 29">7</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=8&amp;q=nike air&amp;th=1" title="Page 8 of 29">8</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=9&amp;q=nike air&amp;th=1" title="Page 9 of 29">9</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=10&amp;q=nike air&amp;th=1" title="Page 10 of 29">10</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=11&amp;q=nike air&amp;th=1" title="Page 11 of 29">11</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=12&amp;q=nike air&amp;th=1" title="Page 12 of 29">12</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=13&amp;q=nike air&amp;th=1" title="Page 13 of 29">13</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=14&amp;q=nike air&amp;th=1" title="Page 14 of 29">14</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=15&amp;q=nike air&amp;th=1" title="Page 15 of 29">15</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=16&amp;q=nike air&amp;th=1" title="Page 16 of 29">16</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=17&amp;q=nike air&amp;th=1" title="Page 17 of 29">17</a> </span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=18&amp;q=nike air&amp;th=1" title="Page 18 of 29">18</a> </span> <span class="nav-active"><strong>19</strong></span> <span class="non-active nohistory"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=20&amp;q=nike air&amp;th=1" title="Page 20 of 29">20</a> </span </span> <span class="nav-next-btn nohistory FloatRight"> <span class="nav-next-btn nohistory marginRight"> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=20&amp;q=nike air&amp;th=1" title="Go to next page"> Next › </a> </span> <a href="http://www.mudah.my/Malaysia/nike+air-for-sale?o=29&amp;q=nike air&amp;th=1" title="Go to last page"> Last » </a> </span> </div> """# 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