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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"{\$(\w+|\w+\|\w+)}"; string input = @"<!DOCTYPE html> <html> <head> <meta charset=""utf-8""> <meta name=""robots"" content=""index,follow""> <meta name=""keywords"" content=""kamerki, erotyczne""> <meta name=""description"" content=""Eroticam.pl""> <link rel=""shortcut icon"" href=""/favicon.ico"" type=""image/x-icon""> <title>Strona główna | Eroticam.pl</title> <base href=""{$_template_root|small_letters}""> <meta property=""og:url"" content=""{$_template_root}""/> <meta property=""og:site_name"" content=""eroticam.pl""/> <meta property=""og:title"" content=""Strona główna | Eroticam.pl""/> <meta property=""og:type"" content=""profile""/> <meta property=""og:image"" content=""/img/logo_big.jpg"" /> <meta property=""og:description"" content=""Opis strony""/> <script src=""{$_template_root}/js/libs/console.js""></script> <script src=""{$_template_root}/js/libs/broadcast.js""></script> <script src=""https://cdn.socket.io/socket.io-1.3.5.js""></script> <script src=""//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js""></script> <script src=""//ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/jquery-ui.min.js""></script> <script src=""{$_template_root}/js/jquery.fancybox.pack.js""></script> <link rel=""stylesheet"" href=""{$_template_root}/css/components.css""> <link rel=""stylesheet"" href=""{$_template_root}/css/default/style.css""> <link rel=""stylesheet"" href=""{$_template_root}/css/default/responsive.css""> <link rel=""stylesheet"" href=""{$_template_root}/css/jquery.fancybox.css""> <link rel=""stylesheet"" href=""{$_template_root}/css/unoSlider.css"" type=""text/css"" media=""screen"" /> <link rel=""stylesheet"" href=""//ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/themes/smoothness/jquery-ui.css"" /> <meta name=""viewport"" content=""width=device-width, initial-scale=1""> <meta name=""google-site-verification"" content=""1tqMv6H9GEsFbXTZaW8zcngUGvqorZ94csA1v7Nc2qg"" /> </head> <body>"; foreach (Match m in Regex.Matches(input, pattern)) { Console.WriteLine("'{0}' found at index {1}.", m.Value, m.Index); } } }

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 C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx