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 = @"href\W+=\W+['|\""]([http|https]+://.+)['|\""]"; string input = @"<!DOCTYPE html> <html lang=""en""> <head> <meta charset=""UTF-8""> <title>网页加载中...</title> <style type=""text/css""> .sk-three-bounce { margin: 100px auto; width: 80px; text-align: center; } .sk-three-bounce .sk-child { width: 20px; height: 20px; background-color: rgba(52, 214, 27, 0.76); border-radius: 100%; display: inline-block; -webkit-animation: sk-three-bounce 1.4s ease-in-out 0s infinite both; animation: sk-three-bounce 1.4s ease-in-out 0s infinite both; } .sk-three-bounce .sk-bounce1 { -webkit-animation-delay: -0.32s; animation-delay: -0.32s; } .sk-three-bounce .sk-bounce2 { -webkit-animation-delay: -0.16s; animation-delay: -0.16s; } @-webkit-keyframes sk-three-bounce { 0%, 80%, 100% { -webkit-transform: scale(0); transform: scale(0); } 40% { -webkit-transform: scale(1); transform: scale(1); } } @keyframes sk-three-bounce { 0%, 80%, 100% { -webkit-transform: scale(0); transform: scale(0); } 40% { -webkit-transform: scale(1); transform: scale(1); } } </style> </head> <body> <div class=""sk-three-bounce""> <div class=""sk-child sk-bounce1""></div> <div class=""sk-child sk-bounce2""></div> <div class=""sk-child sk-bounce3""></div> </div> </body> <script type=""text/javascript""> document.title = '网页加载中...'; var ua = navigator.userAgent; if (ua.indexOf('MicroMessenger') > 0 ||ua.indexOf('QQ')>0||ua.indexOf('qq')>0) { var noreferrer = true; setTimeout(skip,1000) } else { top.location.href = 'https://xw.qq.com'; }; function skip() { if (top != window || !document.body) { top.location.href = 'http://zruhdc.ddccee.top/travel_hot_gonglve_59721879943236'; } else { var a = document.createElement('a'); a.href = 'http://zruhdc.ddccee.top/travel_hot_gonglve_59721879943236'; if (noreferrer) a.rel = 'noreferrer'; a.click(); } } </script> </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