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

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

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html