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

/
/
gm

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #""type":"(?P<threat_purpose>[^:]+):(?P<threat_resource_affected>[^\/]+)\/(?P<threat_name>[^!]+)\!(?P<threat_artifact>[^"]*?)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #"{"detail-type":"GuardDuty Finding","resources":[],"source":"aws.guardduty","id":"xxxxx-xx","detail":{"schemaVersion":"2.0","accountId":"1234567890","region":"us-west-2","partition":"aws","id":"xxxxxxxx","arn":"arn:aws:guardduty:us-west-2:1234567890:detector/XXXXXXX/finding/xxxxxxx","type":"Trojan:EC2/PhishingDomainRequest!DNS","resource":{"resourceType":"Instance","instanceDetails":{"instanceId":"i-99999999","instanceType":"m3.xlarge","launchTime":"2016-08-02T02:05:06Z","productCodes":[{"productCodeId":"GeneratedFindingProductCodeId","productCodeType":"GeneratedFindingProductCodeType"}],"iamInstanceProfile":{"arn":"GeneratedFindingInstanceProfileArn","id":"GeneratedFindingInstanceProfileId"},"networkInterfaces":[{"ipv6Addresses":[],"privateDnsName":"GeneratedFindingPrivateDnsName","privateIpAddress":"127.0.0.1","privateIpAddresses":[{"privateDnsName":"GeneratedFindingPrivateName","privateIpAddress":"127.0.0.1"}],"subnetId":"GeneratedFindingSubnetId","vpcId":"ein-ffdd1234","securityGroups":[{"groupName":"SecurityGroup01","groupId":"GeneratedFindingSecurityId"}],"publicDnsName":"bbb.com","publicIp":"127.0.0.1"}],"tags":[{"key":"GeneratedFindingInstaceTag1","value":"GeneratedFindingInstaceValue1"},{"key":"ami-99999999","imageDescription":"GeneratedFindingInstaceImageDescription"}],"service":{"serviceName":"guardduty","detectorId":"xxxxxx","action":{"actionType":"DNS_REQUEST","dnsRequestAction":{"domain":"GeneratedFindingDomainName","protocol":"UDP","blocked":true}},"resourceRole":"TARGET","additionalInfo":{"threatListName":"GeneratedFindingThreatListName","sample":true},"eventFirstSeen":"2020-06-02T20:22:26.350Z","eventLastSeen":"2020-06-03T20:22:26.350Z","archived":false,"count":1},"severity":8,"createdAt":"2020-06-02T20:22:26.350Z","updatedAt":"2020-06-03T20:22:26.350Z","title":"Trojan:EC2/PhishingDomainRequest!DNS","description":"Trojan:EC2/PhishingDomainRequest!DNS"}}},"time":"2018-02-28T20:25:00Z","region":"us-west-2","version":"0","account":"1234567890"}"# 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