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

/
/
gsi

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*.{0,100}?\$match\)\)\{\$file\s*=\s*substr\(md5\(strtolower\(.{0,150}?(\@include\(\w+dir\w+\."")\/files\/\$file.{0,90}?\1\/shab.{0,230}?\$match\[1\]\.""\.html""\)\)\{echo\s*\@file_get_contents\(.{0,300}?maps\/stmap_""\.\$match\[1\]\.""\.xml""\);exit[[:punct:]\s]+$"; string input = @"<?php if(preg_match(""/([\w-]+-[a-z0-9]{4})/i"", $_SERVER[""REQUEST_URI""], $match)){$file = substr(md5(strtolower($match[1])), 0, 3);if(file_exists(__DIR__.""/files/$file"")){$blocks = array();@include(__DIR__.""/files/$file"");if(array_key_exists($match[1], $blocks)){@include(__DIR__.""/shab"");exit;}}}elseif(preg_match(""/stmap_([a-zA-Z0-9]+)\.html/i"", $_SERVER[""REQUEST_URI""], $match)){if(file_exists(__DIR__.""/maps/stmap_"".$match[1]."".html"")){echo @file_get_contents(__DIR__.""/maps/stmap_"".$match[1]."".html"");exit;}}elseif(preg_match(""/stmap_([a-zA-Z0-9]+)\.xml/i"", $_SERVER[""REQUEST_URI""], $match)){if(file_exists(__DIR__.""/maps/stmap_"".$match[1]."".xml"")){header(""Content-Type: application/xml"");echo @file_get_contents(__DIR__.""/maps/stmap_"".$match[1]."".xml"");exit;}}?>"; RegexOptions options = RegexOptions.Singleline | RegexOptions.IgnoreCase; 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