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

/
/
g

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?<opening>\b(?<montage>[a-zA-Z]:[\/\\])|[\/\\][\/\\](?<!http:\/\/)(?<!https:\/\/)(?>[?.][\/\\](?:[^\/\\<>:"|?\n\r ]+[\/\\])?(?&montage)?|(?!(?&montage)))|%\w+%[\/\\]?)(?:[^\/\\<>:"|?\n\r ,'][^\/\\<>:"|?\n\r]*(?<![ ,'])[\/\\])*(?:(?=[^\/\\<>:"'|?\n\r;, ])(?:(?:[^\/\\<>:"|?\n\r;, .](?: (?=[\w\-]))?(?:\*(?!= ))?(?!(?&montage)))+)?(?:\.\w+)*)|(?:'(?&opening)(?=.*'\W|.*'$)(?:[^\/\\<>:'"|?\n\r]+(?:'(?=\w))?[\/\\]?)*')|"(?&opening)(?=.*")(?:[^\/\\<>:"|?\n\r]+[\/\\]?)*""# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" THIS IS SINGLE LINE VERSION to understand and edit it, go https://regex101.com/r/7o2fyy C:/testOk\dot.Dirname/.nameFileBeginByDot first space after a dot in file name stop the match C:/testOk\_.._AsDirName/../file name.ext1.ext2 first space after a dot stop the match start text don't match C:/testOk\lastDir Or FileName WithDouble..dot stop the match C:/testOk\lastDir Or FileName dot ended. stop the match like an end sentence. So, a last name with a space after a dot is not catch C:/testOk\LastNameIs/DirName C:/testOk\2Paths_ _separated/f.ext space after extention stop match C:/testOK\Last_/_isNotmatched/fgfj.gjjb/uhloext/ and [ ,'] after '\' stop match \\127.0.0.1/this', 'isOkInMidDirName\butSimple',' stop match in last DirName or FileName \\.\c:/this exotic path begining work\and\ space after '\' stop the match \\?\c:/this exotic path begining work too\and \space before '\' stop the match too \\testOk/this' - 'is ok in dirName/and - in lastName.ext i:/dir/fileName with a .space before dot stop the match \\?\server1\e:\utilities\\filecomparer\ this double \\ is interpretated as new path @"c:\testOk\double quote character is more permissive/ '' , ; .txt, .ext2", @"\\127.0.0.1\c$\temp\t'est-file.txt, if end double quote is missing, we use unquote match @"\c:\LOCALHOST\c$\ thisIsNotMatched" "temp\test-file.txt", quoted path must have a right opening to be matched @'\\.\c:\temp\te'st-file.txt' simple quoted is ok 'c:\simpleQuoteInsideStill'Match\but' stopMatch if next is space character, 'c:\simpleQuoteInsideStill'Match\but\'stopMatch if is fisrt character after \ 'c:\simpleQuoteInsideStill'Match\but''stopMatch if he is double @"\\?\c:\te ' mp\est-file.txt", @"\\.\UNC\LOCALHOST\c$\temp\test-file.txt", @"\\127.0.0.1\c$\temp\test-file.txt" /\serverName\mix/and\still match" double quote character stop match \\\IfMoreThan2_\_we take only the 2 lasts.ext first space after ext stop the match /testNotMatch/html /testNotMatch.html testNotMatch.html // -> this simple // or \\ is not matched, but this //isMatched ! / -> this simple / is not matched, and this /notMatchedToo b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Custom Data" "b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Custom Data" "\\b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Custom Data" error Message test: --------------------------- Tentative d'accès à C:\Users\tpgz4017\App - Data\Local\Temp\tempShapeFile_CrossWave Calibration Zones - Atoll CrossWave Model.shx après sa fin. --------------------------- local url path : file://C:/Users/Downloads/20220516_32289275_1049383.pdf urlPath : file://p-eco2.rd.fr/vol_H0037_01$/599/livraison/20220516_32289275_1049383.pdf c:\temp\test-file.txt", \\127.0.0.1\c$\temp\test-file.txt", \\LOCALHOST\c$\ temp\test-file.txt", \\LOCALHOST\c$ \temp\test-file.txt", \\.\c:\temp\t\est-file.txt", \\?\c:\temp\test-file.txt", \\.\UNC\LOCALHOST\c$\temp\test-file.txt", \\?\UNC\ServerName\ temp\test-file.txt", \\127.0.0.1\c$\temp\test -file.txt" error Message test: Site0 / 3: - Warning . See log file 'C:\ProgramData\InfoVista\Planet 7.4\7.4\RPE\Log\Plugins\Universal_Model_masked\log_Universal_Model.txt' for details C:/test\gvk.hv/fgfj.gjjb/uhloext : some random text \\b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Polygon\Haguenau\Building\Haguenau hgtfhyt "C:/te-st.html" "C:/te-st.html" gd"dhbcsk "C:/te/dsst.ikpo fdsf "C:\test" "C:// test.html" gd "//te s t/e, llo.html C:/test\f/uhlo/. C://te?st.html b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Custom Data" ; dfsdf "\\b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Custom Data" ; dfsdf "\\ "\\b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Custom Data"Haguenau_Building.tab : Data format of \\b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Polygon\Haguenau\Building\Haguenau Building.* C: is invalid Haguenau_Building.tab : Data format of \\b-renice\sauvegardes\B-HIER\GEO\Geo NetAct Atoll_Planet\UR_Est\Polygon\Haguenau\Building\Haguenau Building.TAB, is invalid Haguenau_Building.tab : Data format of \\b-renice\sauvegardes\B-HIER\GEO\Geo_NetAct_Atoll_Planet\UR_Est\Polygon\Haguenau\Building\Haguenau Buildi*.*ng.*, is invalid C:/test/../hjgbkl C:/test/../hjgbkl.gfgdfgrdgfdgr C:/test/../hjgbkl C:/test.html C://test/ .h/hel,lo.html//test/./hello.html C:/test//hello.html //test //hello.html /test "%tmp%/fsdfs" %tmp%/fsdfs ERROR 8/31/2021 - 6:45:39 PM HighResClutter .RasterFile : \\b-ren ice\sauv egardes\B-HIER\GEO%dsq%\NewJersey_NewYork\DTM\DTM\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil : Le fichier spécifié est introuvable. \\b-ren ice\sauv egardes\..\B-HIER\GEO\NewJersey_NewYork\DTM\DTM\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil C:\b-ren ice\sauv egardes\B-HIER\GEO\NewJersey_NewYork\DTM\DTM\CENTRAL_JERSE..Y_New_York_2 m_Z18N_0_DTM_02_06.bil \\b-ren ice\sauv egardes\B-HIER\GEO\NewJersey_NewYork\DTM\DTM\CENTRAL_JER SE.Y_New_York_2 m_Z18N_0_DTM_02_06.bil. //test.html \\10.1.1.107 //10.1.1.107/test.html //10.1.1.107/te st/hello.html //10.1.1.107/test/hello //test/hello.txt //test/hello.txt. \\.\UNC\Server\Share\Test\Foo.txt \\?\UNC\Server\Share\Test\Foo.txt Pour les chemins UNC de périphérique, la partie serveur/partage forme le volume. Par exemple, dans \\?\server1\e:\utilities\filecomparer\ , la partie serveur/partage est server1\utilities . Ceci est important quand '\\127.0.0.1\c$\temp\test-fi'le.txt' """# 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