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 = #"(?:(^[^:\r\n]+):?[\r\n]+|\G(?!^))\r?\n[^:\r\n]+ : ([^\r\n]+(?:\r?\n(?!.* : )[ \t]+[^\r\n]+)*)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" Windows IP Configuration Host Name . . . . . . . . . . . . : abcmyhost Primary Dns Suffix . . . . . . . : parker.industries Node Type . . . . . . . . . . . . : Hybrid-GLS IP Routing Enabled. . . . . . . . : YES WINS Proxy Enabled. . . . . . . . : YES DNS Suffix Search List. . . . . . : parker1.industries parker2.industries parker3.industries parker4.industries parker5.industries parker6.industries parker7.industries parker8.industries parker9.industries parker10.industries Ethernet adapter Ethernet 5: Connection-specific DNS Suffix . : parker.industries Description . . . . . . . . . . . : Ready 2 Physical Address. . . . . . . . . : 60-11-11-31-09-XY DHCP Enabled. . . . . . . . . . . : NO Autoconfiguration Enabled . . . . : Yes Link-local IPv6 Address . . . . . : AB80::11FG:1KI:LK9F:12N2%19(Preferred) IPv4 Address. . . . . . . . . . . : 111.222.333.444(Preferred) Subnet Mask . . . . . . . . . . . : 255.255.255.0 Lease Obtained. . . . . . . . . . : Monday, November 11, 2019 6:23:03 AM Lease Expires . . . . . . . . . . : Wednesday, November 13, 2019 6:51:30 AM Default Gateway . . . . . . . . . : 111.11.131.1 DHCP Server . . . . . . . . . . . : 111.22.144.199 DHCPv6 IAID . . . . . . . . . . . : 87244642462 DHCPv6 Client DUID. . . . . . . . : 00-01-02-03-04-05-06-07-08-09-10-11-E9-G7 DNS Servers . . . . . . . . . . . : 111.22.111.254 111.22.112.254 111.33.113.254 111.33.114.254 NetBIOS over Tcpip. . . . . . . . : Enabled """# 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