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 = #"\"locId\":\"(?<locId>[^\"]*)\",\"ip\":\"[^\"]*\",\"hostName\":\"[^\"]*\",\"macaddress\":\"(?<macaddress>[^\"]*)\""# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" {"bdy":{"msg":"NitrosApplication_OnLaunched event triggered.","metricName":"AppStart","metricValue":"NitrosApplication_OnLaunched","measuredTime":"00:00:00.7181610"},"hdr":{"level":"Information","timestamp":"2017-03-17T15:00:55.9692895Z","lineNum":0,"userId":"a211ba03eb3aa1","loc":"Store","locId":"0775","ip":"10.434.24.4","hostName":"W-W10ME-7534513","macaddress":"00-16-7F-EE-DD-17","eventid":0,"appVersion":"10.0.2","appName":"L"},"ver":"0.1"} {"bdy":{"msg":"Background Task 'DevicePowerCheckBackgroundTask' is Running..."},"hdr":{"level":"Information","timestamp":"2017-03-17T15:00:55.842Z","fxsrc":"Run","lineNum":53,"loc":"Store","locId":"0320","ip":"10.439.3.11","hostName":"K-W10ME-054232","macaddress":"00-13-7F-13-33-29","eventid":0,"appVersion":"3.0.2","appName":"L"},"ver":"0.1"} {"bdy":{"msg":"SplashPage loaded on back click.","metricName":"PageLoad","metricValue":"SplashPage","measuredTime":"00:00:00.0006669"},"hdr":{"level":"Information","timestamp":"2017-03-17T15:00:55.3022117Z","lineNum":0,"loc":"Store","locId":"0466","ip":"10.111.11.7","hostName":"K-W10ME-3727099","macaddress":"00-15-7E-GE-D2-11","eventid":0,"appVersion":"16.2.0","appName":"L"},"ver":"0.1"} """# 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