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. Click here to read more.
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

Generated Code

re = /(?:(?:^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)?))/m str = '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 ' # Print the match result str.scan(re) do |match| puts match.to_s end

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html