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 = #"\"event_sub_type\":\"((WAN\s+Firewall)|TLS)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" 1. event_sub_type":"WAN {"event_count":1,"ISP_name":"Shanghai internet","rule":"Initial Connectivity Rule","dest_is_site_or_vpn":"Site","src_isp_ip":"0.0.0.0","time_str":"2023-11-28T04:27:40Z","src_site":"CHINA-AZURE-E2","src_ip":"0.0.0.1","internalId":"54464646","dest_site_name":"china_112,"event_type":"Security","src_country_code":"CN","action":"Monitor","subnet_name":"cn-001.net-vnet-1","pop_name":"Shanghai_1","dest_port":443,"dest_site":"china_connect","rule_name":"Initial Connectivity Rule","event_sub_type":"WAN Firewall","insertionDate":1701188916690,"ip_protocol":"TCP","rule_id":"101238","src_is_site_or_vpn":"Site","account_id":5555,"application":"HTTP(S)","src_site_name":"china_connect","src_country":"China","dest_ip":"0.0.0.0","os_type":"OS_ANDROID","app_stack""TCP","TLS","HTTP(S)"],"time":1701188860834} 2. "event_sub_type":"TLS"," {"event_count":4,"http_host_name":"isp.vpn","ISP_name":"China_internet","src_isp_ip":"0.0.0.0","tls_version":"TLSv1.3","time_str":"2023-11-28T04:27:16Z","src_site":"china_mtt","src_ip":"0.0.0.0","internalId":"rtrgrtr","domain_name":"china.gh.com","event_type":"Security","src_country_code":"CN","tls_error_description":"unknown CA","action":"Alert","subnet_name":"0.0.0.0/24","pop_name":"china_1","dest_port":443,"event_sub_type":"TLS","insertionDate":1701188915580,"dest_country_code":"SG","tls_error_type":"fatal","dns_name":"china.com","traffic_direction":"OUTBOUND","src_is_site_or_vpn":"Site","account_id":56565,"application":"Netskope","src_site_name":"CHINA-44","src_country":"China","dest_ip":"0.0.0.0","os_type":"OS_WINDOWS","time":1701188836011,"dest_country":"Singapore"} """# 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