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

/
/
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?<=<!-- Template Nav Start -->[\n])([\n\s\S]*?)(?=[\s\n]*?<!-- Template Nav End -->)"; string input = @"<!DOCTYPE html> <html lang=""en""> <head> <meta charset=""UTF-8""> <meta http-equiv=""X-UA-Compatible"" content=""IE=edge""> <meta name=""viewport"" content=""width=device-width, initial-scale=1.0""> <meta property=""og:site_name"" content=""WD Proposal""> <meta property=""og:title"" content=""Your new outdoor living space.""> <meta property=""og:image"" content=""https://www.WhitmerDecks.com/Proposal/eProposal/img/wdLogoName.png""> <meta property=""og:description"" content=""Here you can view the proposal from Whitmer Decks, LLC""> </meta> <!-- General scripts & styles --> <link rel=""stylesheet"" href=""css/styles.css""> <link rel=""stylesheet"" href=""css/cwBootstrap.css""> <script src=""js/cwBootstrap.js"" defer></script> <!-- Google Fonts --> <link href=""https://fonts.googleapis.com/css?family=Roboto:300,400,500,700&display=swap"" rel=""stylesheet""> <!-- Page title and end of general head --> <title>WD Proposal</title> <!-- Page specific scripts and styles --> <script src=""js/about.js"" defer></script> </head> <body> <!-- Template Nav Start --> <nav> <ul> <li><a href=""index.html"">Home</a></li> <li><a href=""about.html"">About</a></li> <li>Item X</li> <li>Item Y</li> </ul> </nav> <!-- Template Nav End --> <p> The about page </p> </body> </html>"; 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