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

/
/
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<link rel=""canonical"" href=""(.*?)"">"; string input = @"const regex = /""sku"": ""(.*?)""/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('""sku"": ""(.*?)""', 'gm') const str = ``<!DOCTYPE html> <!-- saved from url=(0044)https://www.daz3d.com/karmen-9-hd-pro-bundle --> <html xmlns=""http://www.w3.org/1999/xhtml"" xml:lang=""en"" lang=""en"" class=""><head><meta http-equiv=""Content-Type"" content=""text/html; charset=UTF-8""> <title>Karmen 9 HD Pro Bundle | Daz 3D</title> <meta name=""viewport"" content=""width=device-width, initial-scale=1""> <meta name=""description"" content=""&lt;p&gt;Introducing the Karmen 9 HD Pro Bundle. This all-inclusive bundle features a vibrant makeup look, expressions, a curly and braided bun hairstyle, apocalyptic-inspired outfits, Elemental Mage and Shadow Realm attire, and even monstrous poses to immerse ""> <meta name=""keywords"" content=""Karmen 9 HD Pro Bundle""> <meta http-equiv=""X-UA-Compatible"" content=""IE=edge""> <meta name=""robots"" content=""INDEX,FOLLOW,noai, noimageai""> <link rel=""icon"" href=""https://www.daz3d.com/static/images/favicon.ico"" type=""image/x-icon""> <link rel=""shortcut icon"" href=""https://www.daz3d.com/static/images/favicon.ico"" type=""image/x-icon""> <!--[if lt IE 7]> <script type=""text/javascript""> //<![CDATA[ var BLANK_URL = '/js/blank.html'; var BLANK_IMG = '/js/spacer.gif'; //]]> </script> <![endif]--> <link rel=""stylesheet"" href=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/design-533ce80c63b6085aedc802b14d1faa79.css"" about=""0""> <link rel=""stylesheet"" href=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/product_zoom-5de5dd875434871413473d85f684dcfc.css"" about=""1""> <style> @keyframes spinner { 0% { transform: translateY(-50%) rotate(0deg); } 100% { transform: translateY(-50%) rotate(360deg); } } .spinner::after { animation: 1.5s linear infinite spinner; animation-play-state: inherit; border: solid 3px #cfd0d1; border-bottom-color: #1c87c9; border-radius: 50%; content: ""; height: 20px; width: 20px; display: inline-flex; flex-direction: column; padding-bottom: 5px; } </style> <script src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/getIds"" type=""text/javascript"" async=""></script><script type=""text/javascript"" id=""www-widgetapi-script"" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/www-widgetapi.js.download"" async=""></script><script async="" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/fbevents.js.download""></script><script type=""text/javascript"" async="" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/bat.js.download""></script><script type=""text/javascript"" async="" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/pixel.js.download""></script><script type=""text/javascript"" async="" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/analytics.js.download""></script><script type=""text/javascript"" async="" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/js""></script><script type=""text/javascript"" async="" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/destination""></script><script src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/tag.js.download"" type=""text/javascript"" async="" id=""cjapitag""></script><script async="" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/affirm.js.download""></script><script type=""text/javascript"" async="" src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/0""></script><script src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/core-ed1ca31447e4f2e9bbf6d9ef38afe3c6.js.download""></script> <style> @keyframes spinner { 0% { transform: translateY(-50%) rotate(0deg); } 100% { transform: translateY(-50%) rotate(360deg); } } .spinner::after { animation: 1.5s linear infinite spinner; animation-play-state: inherit; border: solid 3px #cfd0d1; border-bottom-color: #1c87c9; border-radius: 50%; content: ""; height: 20px; width: 20px; display: inline-flex; flex-direction: column; padding-bottom: 5px; } </style> <script src=""./Karmen 9 HD Pro Bundle _ Daz 3D_files/zoom-fee76dde1f2c855960b29036b231c115.js.download""></script> <script type=""application/ld+json"">{ ""brand"": { ""name"": ""Daz 3D"", ""@type"": ""Brand"" }, ""@context"": ""https://schema.org/"", ""description"": ""Introducing the Karmen 9 HD Pro Bundle. This all-inclusive bundle features a vibrant makeup look, expressions, a curly and braided bun hairstyle, apocalyptic-inspired outfits, Elemental Mage and Shadow Realm attire, and even monstrous poses to immerse your character into any narrative from modern desert to fantasy to horror."", ""image"": ""https://gcdn.daz3d.com/p/91909/i/shimuzu_Karmen_Pro_Bundle.jpg"", ""name"": ""Karmen 9 HD Pro Bundle"", ""offers"": { ""availability"": ""https://schema.org/InStock"", ""itemCondition"": ""https://schema.org/NewCondition"", ""price"": 185.99, ""priceCurrency"": ""USD"", ""@type"": ""Offer"" }, ""sku"": ""91909"", ""@type"": ""Product"" }</script> <link rel=""canonical"" href=""https://www.daz3d.com/karmen-9-hd-pro-bundle""> <script> if (!daz) { var daz = {}; }; daz.api = new DazApi() from 331.2deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 93% { border-image: conic-gradient( from 334.8deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 94% { border-image: conic-gradient( from 338.4deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 95% { border-image: conic-gradient( from 342deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 96% { border-image: conic-gradient( from 345.6deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 97% { border-image: conic-gradient( from 349.2deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 98% { border-image: conic-gradient( from 352.8deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 99% { border-image: conic-gradient( from 356.4deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } 100% { border-image: conic-gradient( from 360deg, var(--border-color-1), var(--border-color-2), var(--border-color-1), var(--border-color-2), var(--border-color-1) ) 1; } } } /* END rotate bonus box border */ /* BEGIN falling stars animation */ .bg-stars { width: 100%; height: 100%; position: absolute; top: 0; left: 0; overflow: hidden; } .bg-stars .bg-star { font-size: 1em; position: absolute; top: -25px; color: yellow; user-select: none; cursor: default; text-shadow: 0 0 1px #000; animation-name: fallingStars; animation-duration: 5s; animation-timing-function: linear; animation-iteration-count: infinite; animation-play-state: running; z-index: -1; } .bg-stars .bg-star:nth-of-type(1) { left: 10%; -webkit-animation-delay: 1s, 1s; animation-delay: 1s, 1s; } .bg-stars .bg-star:nth-of-type(2) { left: 20%; </div></body></html>(`; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); } "; RegexOptions options = RegexOptions.Multiline; foreach (Match m in Regex.Matches(input, pattern, options)) { 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