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

r"""
"""
gm

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\bEmail:\s*<a\s[^<>]*\bhref=""mailto:([^""]+)"""; string input = @"<!DOCTYPE html PUBLIC ""-//W3C//DTD XHTML 1.0 Transitional//EN"" ""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd""> <html xmlns=""http://www.w3.org/1999/xhtml""> <html> <head></head> <body> <a name=""top""></a>Back to Category Index</a></p> <p>-----------------------------------<br/></p> 67)<a name=""e1h1"" id=""e1h1""></a> Summary: Solar Eclipse 2024 Travel <br/><br/> <p>Name: laure gem wilson Roadtrippers </p>Category: Travel <br/><br/> Email: <a href=""mailto:query-e1h1@email.net"">query-e1h1@email.net</a> <br/><br/> Outlet: Roadtrip<br/><br/> Deadline: 7:00 PM EST - 8 July <br/><br/> <p> Query: <br/><br/> Hi, I am on assignment to write a feature about planning a road<br/>trip to experience the Solar Eclipse 2024, including path of<br/>totality, advice about viewing, and recommendations for when and<br/>where to book accommodations, thanks!<br/> </p> <p> Requirements: <br /><br /> Must be domestic USA<br/> </p> <p><a href=""#top"">Back to Top</a> <a href=""#Travel"">Back to Category Index</a></p> <p>-----------------------------------<br/> "; 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