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

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\<(\w+)(?:\s*|\>)?"; string input = @" <!DOCTYPE html> <html lang=""el"" dir=""ltr"" class=""no-js""> <head> <meta charset=""utf-8"" /> <title>Radial</title> <meta name=""description"" content=""Η Radial σχεδιάζει και αναπτύσσει websites, οργανώνει online καμπάνιες και δημιουργεί εταιρικές ταυτότητες."" /> <meta property=""fb:page_id"" content=""118981334805256"" /> <meta property=""fb:app_id"" content=""166019300145537"" /> <!--[if lt IE 9]><script type=""text/javascript"" src=""http://html5shiv.googlecode.com/svn/trunk/html5.js""></script><![endif]--> <script type=""text/javascript"">(function(H){H.className=H.className.replace(/\bno-js\b/,'js')})(document.documentElement);</script> <link rel=""stylesheet"" type=""text/css"" media=""screen"" href=""http://static.radial.gr/styles/screen.css?43614"" /> <script type=""text/javascript"" src=""http://use.typekit.com/ioa2dxy.js""></script> <script type=""text/javascript"">try{Typekit.load();}catch(e){}</script? <link rel=""alternate"" type=""application/rss+xml"" title=""Τελευταία έργα"" href=""/feed/"" /> </head> <body id=""home"" class=""> <header id=""main-header""><div class=""wrapper""> <div id=""logo""><a href=""/""><img src=""http://static.radial.gr/images/radial-logo.png"" alt=""Radial"" /></a></div> <nav id=""main-nav""> <ul> <li><a href=""/projects/"">Έργα</a></li> <li><a href=""/profile/"">Προφίλ</a></li> <li><a href=""/contact/"">Επικοινωνία</a></li> </ul> </nav> <nav id=""lang-nav""> <span>EΛ</span> <a href=""/en/"">EN</a> </nav> <br /> </div></header> <script type=""text/javascript""> var _gaq = _gaq || []; _gaq.push(['_setAccount', 'UA-515952-44']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); </script> </body> </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