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

Substitution

Processing...

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?<=class=[""'][\w\- :\.]*)([\w\-:\.]+)"; string substitution = @""; string input = @"<div class=""px-4 sm:px-6 lg:px-8""> <div class=""sm:flex sm:items-center""> <div class=""sm:flex-auto""> <h1 class=""text-xl font-semibold text-gray-900"">Users</h1> <p class=""mt-2 text-sm text-gray-700"">A list of all the users in your account including their name, title, email and role.</p> </div> <div class=""mt-4 sm:mt-0 sm:ml-16 sm:flex-none""> <button type=""button"" class=""inline-flex items-center justify-center rounded-md border border-transparent bg-indigo-600 px-4 py-2 text-sm font-medium text-white shadow-sm hover:bg-indigo-700 focus:outline-none focus:ring-2 focus:ring-indigo-500 focus:ring-offset-2 sm:w-auto"">Add user</button> </div> </div> <div class=""mt-8 flex flex-col""> <div class=""-my-2 -mx-4 overflow-x-auto sm:-mx-6 lg:-mx-8""> <div class=""inline-block min-w-full py-2 align-middle""> <div class=""overflow-hidden shadow-sm ring-1 ring-black ring-opacity-5""> <table class=""min-w-full divide-y divide-gray-300""> <thead class=""bg-gray-50""> <tr> <th scope=""col"" class=""py-3.5 pl-4 pr-3 text-left text-sm font-semibold text-gray-900 sm:pl-6 lg:pl-8"">Name</th> <th scope=""col"" class=""px-3 py-3.5 text-left text-sm font-semibold text-gray-900"">Title</th> <th scope=""col"" class=""px-3 py-3.5 text-left text-sm font-semibold text-gray-900"">Email</th> <th scope=""col"" class=""px-3 py-3.5 text-left text-sm font-semibold text-gray-900"">Role</th> <th scope=""col"" class=""relative py-3.5 pl-3 pr-4 sm:pr-6 lg:pr-8""> <span class=""sr-only"">Edit</span> </th> </tr> </thead> <tbody class=""divide-y divide-gray-200 bg-white""> <tr> <td class=""whitespace-nowrap py-4 pl-4 pr-3 text-sm font-medium text-gray-900 sm:pl-6 lg:pl-8"">Lindsay Walton</td> <td class=""whitespace-nowrap px-3 py-4 text-sm text-gray-500"">Front-end Developer</td> <td class=""whitespace-nowrap px-3 py-4 text-sm text-gray-500"">lindsay.walton@example.com</td> <td class=""whitespace-nowrap px-3 py-4 text-sm text-gray-500"">Member</td> <td class=""relative whitespace-nowrap py-4 pl-3 pr-4 text-right text-sm font-medium sm:pr-6 lg:pr-8""> <a href=""#"" class=""text-indigo-600 hover:text-indigo-900"">Edit<span class=""sr-only"">, Lindsay Walton</span></a> </td> </tr> <!-- More people... --> </tbody> </table> </div> </div> </div> </div> </div>"; RegexOptions options = RegexOptions.Multiline; 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