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
Processing...

Test String

Substitution
Processing...

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^(PageTitle = ""([^""]*)"")(.*)(<title>)([^<]*)(<\/title>)(.*)(<h1 id=""page-title"" class=""font-36"">)([^<]*)(<\/h1>)(.*)$"; string substitution = @"$1$3$4$2$6$7$8$2$10$11"; string input = @"<!-- and this include too --> Must include all this too <% PageTitle = ""Member Access"" MetaDescription = ""There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology"" Keywords = ""SOT, Toxicology, Careers, Resource Guide"" SocialImage = ""http://209.183.221.233/images/sot_logo.png"" SocialImageDescription = ""SOT logo"" SocialURL = ""http://209.183.221.233/login.asp"" %> <!doctype html> <html dir=""ltr"" lang=""en""> <head> <meta charset=""UTF-8""> <!-- Meta Tags --> <meta name=""description"" content=""There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology""> <meta name=""keywords"" content= ""SOT, Toxicology, Careers, Resource Guide""> <meta name=""viewport"" content=""width=device-width, initial-scale=1.0 shrink-to-fit=no""> <meta name=""author"" content=""Society of Toxicology"" /> <meta name =""robots"" content=""index"" > <!-- Twitter and Facebook Social media tags --> <meta property=""fb:app_id"" content=""309282950004135"" /> <meta property=""og:title"" content=""New Experiences in Toxicology Program"" > <meta property=""og:description"" content=""There are a number of degree and education paths that can lead an individual to a career in toxicology. This page is designed to provide those considering a career in toxicology with information on the profession, schooling needed, and more. The content of this page was originally developed as a printed publication called Resource Guide to Careers in Toxicology""> <meta property=""og:image"" content=""http://209.183.221.233/images/sot_logo.png""> <meta property=""og:url"" content=""http://209.183.221.233/education/st/next.asp""> <meta property=""og:type"" content=""website"" /> <!-- Non-Essential, But Recommended --> <meta property=""og:site_name"" content=""Society of Toxicology""> <meta name=""twitter:card"" content=""summary_large_image""> <meta name=""twitter:image:alt"" content= ""SOT logo""> <meta name=""twitter:creator"" content=""@SOToxicology"" /> <!-- Non-Essential, But Required for Analytics --> <meta name=""twitter:site"" content=""@SOToxicology""> <!-- Follow Facebook's recommendation of a minimum dimension of 1200x630 pixels and an aspect ratio of 1.91:1, but adhere to Twitter's file size requirement of less than 1MB.--> <!-- Page Title --> <title>New Experiences in Toxicology Program</title> <!-- #include virtual=""/_includes/header_newsite_trt.asp"" --> <div id=""main"" class=""main-content""> <section class=""inner-header divider layer-overlay overlay-dark-4"" data-bg-img=""/images/_interior-banners/About-banner.jpg"" style=""background-image: url('/images/_interior-banners/About-banner.jpg'); ""> <div class=""container pt-30 pb-30""> <!-- Section Content --> <div class=""section-content""> <div class=""row""> <div class=""col-md-6""> <h1 id=""page-title"" class=""font-36"">New Experiences in Toxicology Program</h1> <ol class=""breadcrumb text-left mt-10 white""> <li class=""active"">New Experiences in Toxicology Program</li> </ol> </div> </div> </div> </div> </section> <!-- #include virtual=""/_includes/social-buttons.asp"" --> <!-- Indvidual Page Content Below --> <!-- #include virtual=""/_global/SOTLogin.asp"" --> <!-- Section: Paragraph ---> <section> <div class=""container ""> <div class=""section-content""> <CENTER> <TABLE width=500> <TR> <TD height=""0"" width=""226""></TD> <TD width=""108""></TD> </TR> <TR> <TD height=""211"" valign=""top""> <TABLE > <TR> <TD align=center height=""185""> <noscript> Javascript not enabled. <BR>Membership functions are not available. </noscript> <% If Request.Cookies(""sot-session-id"") <> "" Then %> <h3>You are now logged in.<br>Please wait for the page to be redirected.</h3> <meta http-equiv='refresh' content='1;url=/'> <% End If %> </font></TD> </TR> </TABLE> </TD> <TD height=""211""></TD> </TR> </TABLE> </CENTER> </div> <!-- /columns --> </div> </section> <!-- /section Full paragraph ends--> <!-- #include virtual=""/_includes/footer.asp"" --> "; RegexOptions options = RegexOptions.Multiline | RegexOptions.Singleline; Regex regex = new Regex(pattern, options); string result = regex.Replace(input, substitution); } }

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