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"
"
gm

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?<!\d)(?:\d{12}|\d{8})\.?(?:[0-9xX])(?!\d)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" 申请号 002623110 022879803 2004100184779 2004100666004 2005101110245 2006300002925 2006200007177 2007100385983 2008101335952 2008101613271 2011100997897 2008201400425 2009101423229 2009101423233 2009101423248 2009101439477 2009101572384 2009101572399 2009101576224 2009302031381 2009101610776 2009201695623 2011200054060 2011200115844 2011200117483 2011200119760 2011200173252 2009202675059 2009202695692 2010101657760 2010101870386 2010102394457 2010102394599 2010202748438 2010202748442 2010202748461 2010305347887 2010305348019 201120005687X 2011200119900 2011200173290 2010105277084 2010105566205 2011200349620 2011100914818 2011100914945 2011101671599 2011202170507 2011303345684 2011103392345 2011204598533 2011204598548 201120459882X 2011204728081 2011204728185 2011103986574 201220034593X 2012200534787 2012101185754 2012201875401 2012101522194 2012101616153 201210181171X 201210182746X 2012302578183 2012102717768 2012204355254 2012103245533 201210339474X 2012103530528 2012103625443 2012103785724 2012205133542 2012306400917 2013100109283 2013100347741 2013200572675 2013100686967 2013100887627 201310101959X 2013204392703 2013103116132 2013204821094 2013103430914 2013205073300 201320567066X 2013205672542 2013104198233 2013205697728 201310438266X 2013206047657 2013206784136 2013106979478 2013107401728 2013208786475 2014100017892 2014203613224 2014103129866 2014103129917 2014203668496 2014103211663 2014103512302 2014104555767 2014205304935 2014104903341 2014104919602 2014205488892 201420580619X 2014106419682 2014206836544 2014107834019 2014305467389 2015203286585 2015203324750 201510275816X 2015103420381 2015103500672 2015103696669 2015204541209 2015204664745 2015103923075 201510467622X 2015205745010 2015205769284 2015207387890 2015207443706 2015106236775 201510624713X 2015207542082 2015207551452 2015207556085 2015110314940 2015211349209 2015211360104 2015211381702 2016100727763 201610092328X 2016201269151 2016100951186 201620131265X 2016101122274 2016201537615 2016202566259 2016102311131 2016205198507 2016105865929 2016207787667 2016207928858 2016207951375 2016208270639 2016208319490 2016106880470 2016106880555 2016209033823 201621066422X 2016108656802 2016210939684 2016305258880 2016305258895 2017100585076 2017100586609 201720188818X 2017101518115 2017202603036 2017204977946 2017205042156 2017103350053 2017205395444 2017206736253 2017302335447 2017104425076 2017106763096 201721030029X 2017210381102 2017108045288 2017108474438 2017212101341 2017108741867 2017108759339 2017212638027 201710920118X 201710937864X 201710938025X 2017212918579 2017212918668 2017212919919 2017212920244 2018305555227 2017109935766 201710994526X 2017109953730 201710995375X 2017213675894 2017213676191 2017213684060 2017213691670 2017214075375 2017215966451 201730622561X 2017306229748 2017306232613 2017306232628 2017217386944 2018201916983 2018201917914 2018202592290 201810191260X 2018203227754 2018104322962 2018206790888 2018104373610 2018206885731 2018207863744 201820786380X 2018207884967 2018105251184 201820872835X 2018209012008 2018106635891 2018209871622 2018303397159 2018303401597 2018108107645 2018211712732 2018108434473 2018212145039 201810884066X 2018212612587 2018109232869 2018213117869 2018213118293 2018213129669 2018109730845 2018213745478 2018111137608 2018111199286 2018215601739 2018216540022 2018217340269 2018305943345 2018114173714 201821980006X 201811454311X 201822010483X 2018114822527 201822097698X 2018220978171 2019100186094 201920036562X 2019200056202 2019204835323 2019103446604 2019205950070 2019102993026 2019205043321 2019102887031 2019204926623 2019204495410 2019209514723 2019210406537 2019301669399 2019301669257 2019105752159 2019210048170 2019106651386 2019212083094 """# 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