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 = #"https?:\/\/(?:[^\/]+\/){4}(.*)"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #"https://firstURL/Second/Third/Fourth/five/SearchResults?json=%7B%22SalesInventoryID%22%3Anull%2C%22BundleInventoryID%22%3Anull%2C%22InventorySalesPriceID%22%3Anull%2C%22SiteType%22%3A8%2C%22SiteName%22%3A%22Desert%20Club%22%2C%22PointsMin%22%3A1%2C%22PointsMax%22%3A999999%2C%22RoomType%22%3Anull%2C%22PriceMin%22%3A1%2C%22PriceMax%22%3A999999%2C%22SeasonType%22%3Anull%2C%22FrequencyType%22%3Anull%2C%22CheckInType%22%3Anull%2C%22WeekMin%22%3A1%2C%22WeekMax%22%3A52%2C%22RoomMin%22%3A%221%22%2C%22RoomMax%22%3A%22999999%22%2C%22TourID%22%3A2022154%2C%22TourLocationID%22%3A54%2C%22ListResults%22%3Anull%2C%22BundledResults%22%3Anull%2C%22TourParticipantInfo%22%3A%7B%22TourID%22%3A2022154%2C%22SiteID%22%3A1%2C%22SiteName%22%3Anull%2C%22PersonID%22%3A364182%2C%22FirstName%22%3A%22Lynn%20A.%22%2C%22LastName%22%3A%22McDougald%22%2C%22City%22%3A%22Charlotte%22%2C%22State%22%3A%22-%22%2C%22ShortState%22%3A%22-%22%2C%22Country%22%3Anull%2C%22CountryID%22%3A840%2C%22OwnerNumber%22%3A%226017104%22%2C%22OwnerStatus%22%3Anull%2C"# 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