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

/
/
sg

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"<(?<key>[^>]+)>(?<value>[^<]+)<\/\1>"# let regex = try! NSRegularExpression(pattern: pattern, options: .dotMatchesLineSeparators) let testString = #"[2015-08-10T15:00:03.644+1000] | INFO | cessAuditorEvent | updateNetworkResource | 188 - ib2b-common-lib - 3.0.4074 | 1c679b99-2235-4027-93a5-9f9b91822c77 | 9e9 ib2b-bs-manage-network-resource_3.0.4074 WorkforceManagement NBNTEST01 ? HEADER [activityName="updateNetworkResource", msgName="ManageNetworkResourceupdateNetworkResourceError", businessServiceName="ManageNetworkResource", businessServiceVersion="V1.0", msgType="Error", accessSeekerId="NBNTEST01", replyToURI="SERVICE.BS.MANAGE_NETWORK_RESOURCE.V1.RESP.WWM", activityStatus="Failure", correlationId="1c679b99-2235-4027-93a5-9f9b91822c77", security="Placeholder Security", priority="4", communicationPattern="RequestReply", timestamp="2015-08-10T05:00:03Z", businessChannel="WorkforceManagement", headerCharacteristicValue="[Mocked:TRUE]"] MESSAGE [<?xml version="1.0" encoding="UTF-8"?><soapenv:Fault xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:exp="http://www.nbnco.com.au/cim/common/exception/v5" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:nbnfn="http://www.nbnco.com.au/functions"><faultcode>exp:TechnicalException</faultcode><faultstring>000000: A technical error has occurred during the processing of the request.</faultstring><detail><exp:TechnicalException><Exception><ID>000000</ID><description>A technical error has occurred during the processing of the request.</description><type>Error</type><ReferencesApplicationException><returnType>Technical</returnType><returnCode>PNI-TEC-0003</returnCode><returnDescription>A data issue has prevented the application from processing the request.</returnDescription></ReferencesApplicationException></Exception></exp:TechnicalException></detail></soapenv:Fault>] [jms://queue:SERVICE.BS.MANAGE_NETWORK_RESOURCE.V1.RESP.WWM (12ms taken)] [ExchangeSentEvent]"# 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