Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"
gm

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?:(?:^edit\ \"(.+)\"$\n)(?:^set\ uuid\ ([a-f0-9]{8}\-(?:[a-f0-9]{4}\-){3}[a-f0-9]{12})$\n)(?:(?:^set\ comment\ )((?:(?!^set\ )(?:.*$\n))+)(?=^set\ ))?(?:^set\ service\ (\".+\")$\n)?(?:^set\ extip\ ((?:(?:\d{1,3}\.){3}(?:\d{1,3}))(?:\-(?:\d{1,3}\.){3}(?:\d{1,3}))?)$\n)(?:^set\ extintf\ \"(.+)\"$\n)(?:^(set\ portforward)\ (enable)$\n)?(?:^(set\ color)\ (\d{1,2})$\n)?(?:^set\ mappedip\ \"((?:(?:\d{1,3}\.){3}(?:\d{1,3}))(?:\-(?:\d{1,3}\.){3}(?:\d{1,3}))?)\"$\n)(?:^(set\ protocol)\ (.+)$\n)?(?:^(set\ extport)\ (\d{1,5}(?:\-\d{1,5})?)$\n)?(?:^(set\ mappedport)\ (\d{1,5}(?:\-\d{1,5})?)$\n)?(?:^next$\n(?:^$\n)?))"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" edit "VIP [DNS сервер site.com]" set uuid abcdef01-2345-6789-abcd-ef0123456789 set comment "Публикация IP-адреса для проекта \"TEST\" в ДЦ \"Облако\"" set service "HTTP Webserver" set extip 100.200.254.20 set extintf "DMZ [VLAN 100]" set portforward enable set color 3 set mappedip "10.100.200.5" set protocol udp set extport 53 set mappedport 2000-65535 next edit "VIP [NTP сервер site.com]" set uuid abcdef01-2345-6789-abcd-ef0123456789 set comment "Публикация IP-адреса для проекта \"TEST\" в ДЦ \"Облако\"" set service "NTP TCP Server" "NTP UDP Server" set extip 100.200.254.20-100.200.254.21 set extintf "DMZ [VLAN 100]" set portforward enable set color 3 set mappedip "10.100.200.5-10.100.200.6" set protocol udp set extport 123 set mappedport 1000-1999 next """# 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