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

/
/
g

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"href=""([^""]+)"""; string input = @" <!DOCTYPE html> <html lang=""fr""> <head></head> <body> <div id=""wm-ipp"" class="" lang=""en"" style=""display: block;""></div> <!-- BEGIN WAYBACK TOOLBAR INSERT --> <script src=""/static/js/disclaim-element.js"" type=""text/javascript""></script> <script src=""/static/js/graph-calc.js"" type=""text/javascript""></script> <script src=""/static/jflot/jquery.min.js"" type=""text/javascript""></script> <script type=""text/javascript""></script> <style type=""text/css""></style> <script type=""text/javascript""></script> <!-- END WAYBACK TOOLBAR INSERT --> <header id=""main_header""> <div class=""header_content""></div> </header> <div id=""main_content""> <div id=""under_top_event""></div> <div id=""breadcrumbs""></div> <div id=""main_search""></div> <div id=""content""> <div id=""page_test"" class=""home""> <div id=""topline""> <h1> TESTS </h1> </div> <div class=""large_column left_column""> <a class=""top"" title=""Lire le test : The Final Fantasy"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-65-the-final-fantasy-3ds-page-opinion.html""></a> <div class=""separation"" style=""margin: 20px 0;""></div> <a class=""high"" title=""Lire le test : El Shaddai : Ascension of The Metatron"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-63-el-shaddai-ascension-of-the-metatron-ps3-page-opinion.html""></a> <a class=""high"" title=""Lire le test : Heroes of Ruin"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-62-heroes-of-ruin-3ds-page-opinion.html""></a> <a class=""high"" title=""Lire le test : Prototype 2"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-61-prototype-2-ps3-page-opinion.html""></a> <a class=""high"" title=""Lire le test : Rayman Origins"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-60-rayman-origins-ps3-page-opinion.html""></a> </div> <div class=""medium_column right_column"" style=""padding-top: 70px;""> <a class=""medium"" title=""Lire le test : Mass Effect 3"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-59-mass-effect-3-x360-page-opinion.html""> <span class=""small title""></span> <span class=""put_score score""></span> <span class=""description""></span> </a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Pandora's Tower"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-58-pandoras-tower-wii-page-opinion.html""> <span class=""small title""></span> <span class=""put_score score""></span> <span class=""description""></span> </a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : I am alive"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-57-i-am-alive-x360-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Silent hill downpour"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-56-silent-hill-downpour-ps3-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Naruto Storm Generations"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-55-naruto-storm-generations-x360-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Street Fighter x Tekken"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-54-street-fighter-x-tekken-ps3-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Ninja Gaiden 3"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-53-ninja-gaiden-3-ps3-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Asura's Wrath"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-52-asuras-wrath-ps3-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : The Last Story"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-51-the-last-story-wii-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Xenoblade"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-50-xenoblade-wii-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : SSX"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-48-ssx-ps3-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Syndicate"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-47-syndicate-pc-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Resident Evil Revelations"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-46-resident-evil-revelations-3ds-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Binary Domain"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-45-binary-domain-ps3-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Catherine"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-43-catherine-x360-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> <a class=""medium"" title=""Lire le test : Soulcalibur V"" href=""/web/20121023121603/http://www.gameweb.fr/articles/test-44-soulcalibur-v-ps3-page-opinion.html""></a> <div class=""separation"" style=""margin: 10px 0;""></div> </div> </div> </div> </div> <footer id=""main_footer""></footer> </body> </html> <!-- FILE ARCHIVED ON 12:16:03 oct. 23, 2012 AND … --> "; foreach (Match m in Regex.Matches(input, pattern)) { 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