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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<style>[\s\S]*<\/style>"; string input = @"<!-- * @Descripttion: 打开koroFileHeader查看配置 进行设置: https://github.com/OBKoro1/koro1FileHeader/wiki/%E9%85%8D%E7%BD%AE * @version: April 2021 (version 1.56) * @Author: ZhangKe * @Date: 2022-04-15 11:12:09 * @LastEditors: ZhangKe * @LastEditTime: 2022-04-15 11:20:25 * @FilePath: \19_Node.js\13_clocl时钟案例\index.html --> <!DOCTYPE html> <html lang=""en""> <head> <meta charset=""UTF-8""> <meta name=""viewport"" content=""width=device-width, initial-scale=1.0""> <meta http-equiv=""X-UA-Compatible"" content=""ie=edge""> <title>index首页</title> <style> html, body { margin: 0; padding: 0; height: 100%; background-image: linear-gradient(to bottom right, red, gold); } .box { width: 400px; height: 250px; background-color: rgba(255, 255, 255, 0.6); border-radius: 6px; position: absolute; left: 50%; top: 40%; transform: translate(-50%, -50%); box-shadow: 1px 1px 10px #fff; text-shadow: 0px 1px 30px white; display: flex; justify-content: space-around; align-items: center; font-size: 70px; user-select: none; padding: 0 20px; /* 盒子投影 */ -webkit-box-reflect: below 0px -webkit-gradient(linear, left top, left bottom, from(transparent), color-stop(0%, transparent), to(rgba(250, 250, 250, .2))); } </style> </head> <body> <div class=""box""> <div id=""HH"">00</div> <div>:</div> <div id=""mm"">00</div> <div>:</div> <div id=""ss"">00</div> </div> <script> window.addEventListener('load', function (evt) { // 定时器，每隔 1 秒执行 1 次 setInterval(() => { var dt = new Date() var HH = dt.getHours() var mm = dt.getMinutes() var ss = dt.getSeconds() // 为页面上的元素赋值 document.querySelector('#HH').innerHTML = padZero(HH) document.querySelector('#mm').innerHTML = padZero(mm) document.querySelector('#ss').innerHTML = padZero(ss) }, 1000) }); // 补零函数 function padZero(n) { return n > 9 ? n : '0' + n } </script> </body> </html>"; foreach (Match m in Regex.Matches(input, pattern)) { 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