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

/
/
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(<(?:(?:(?:(script|style|object|embed|applet|noframes|noscript|noembed)(?:\s+(?=((?:""[\S\s]*?""|'[\S\s]*?'|(?:(?!\/>)[^>])?)+))\3)?\s*>)[\S\s]*?<\/\2\s*(?=>))|(?:\/?[\w:]+\s*\/?)|(?:[\w:]+\s+(?:""[\S\s]*?""|'[\S\s]*?'|[^>]?)+\s*\/?)|\?[\S\s]*?\?|(?:!(?:(?:DOCTYPE[\S\s]*?)|(?:\[CDATA\[[\S\s]*?\]\])|(?:--[\S\s]*?--)|(?:ATTLIST[\S\s]*?)|(?:ENTITY[\S\s]*?)|(?:ELEMENT[\S\s]*?))))>)|([^<>]*?)(querry)"; string input = @"<body class=""mediawiki querry ltr sitedir-ltr ns-0 ns-subject page-International_English_Language_Testing_System skin-vector action-view vector-animateLayout""> <div id=""mw-page-base"" class=""noprint""></div> <div id=""mw-head-base"" class=""noprint""></div> <div id=""content"" class=""mw-body"" role=""main""> <a id=""top""></a> and also a normal querry <div id=""siteNotice""><!-- CentralNotice --></div> <h1 id=""firstHeading"" class=""firstHeading"" lang=""en""><span dir=""auto"">International English Language Testing System</span></h1> <div id=""bodyContent"" class=""mw-body-content""> <div id=""siteSub"">From Wikipedia, the free encyclopedia</div> <div id=""contentSub"">  (Redirected from <a href=""/w/index.php?title=IELTS&amp;redirect=no"" title=""IELTS"">IELTS</a>)</div> <div id=""jump-to-nav"" class=""mw-jump""> Jump to: <a href=""#mw-navigation"">navigation</a>, <a href=""#p-search"">search</a> </div> <div id=""mw-content-text"" lang=""en"" dir=""ltr"" class=""mw-content-ltr""><table class=""infobox vevent"" cellspacing=""3"" style=""border-spacing:3px;width:22em;""> <caption class=""summary"">International English Language Testing System</caption> <tr> <td colspan=""2"" style=""text-align:center;""><a href=""/wiki/File:IELTS_logo.svg"" class=""image""><img alt=""IELTS logo.svg"" src=""//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/IELTS_logo.svg/300px-IELTS_logo.svg.png"" width=""300"" height=""113"" srcset=""//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/IELTS_logo.svg/450px-IELTS_logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7f/IELTS_logo.svg/600px-IELTS_logo.svg.png 2x"" data-file-width=""778"" data-file-height=""293"" /></a></td> </tr> <tr> <th scope=""row"" style=""text-align:left;"">Acronym</th> <td>IELTS</td> </tr> <tr> <th scope=""row"" style=""text-align:left;"">Type</th> <td>Standardized test. Available in 2 versions: ""Academic"" and ""General training"".</td> </tr> <tr> <th scope=""row"" style=""text-align:left;"">Developer / administrator</th> <td><a href=""/wiki/Cambridge_English_Language_Assessment"" title=""Cambridge English Language Assessment"">Cambridge English Language Assessment</a>, <a href=""/wiki/British_Council"" title=""British Council"">British Council</a>, <a href=""/wiki/IDP_Education"" title=""IDP Education"">IDP Education</a>.</td> </tr> <tr> <th scope=""row"" style=""text-align:left;"">Knowledge/skill(s) tested</th> <td>Listening, reading, writing and speaking of the <a href=""/wiki/English_language"" title=""English language"">English language</a>.</td> </tr> <tr> <th scope=""row"" style=""text-align:left;"">Purpose</th> <td>To assess the English language proficiency of non-native English speakers.</td> </tr> "; 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