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

/
/

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\{\s*ADDIN ZOTERO_ITEM.*http\:\/\/zotero\.org\/.*items\/([^\""]*).*\}\s*}"; string input = @"The current wave of protests formed through the coming together of three elements. <i>First</i>, some students demonstrated on various university campuses (mainly Táchira) for at least two weeks before the big 12 February 2014 protests. They protested against <i>insecurity</i> and Venezuela’s high crime rates. Vivia Sequera from the Christian Science Monitor claims that students at the University of the Andes were initially protesting an attempted rape of a young woman on campus.<a title="" href=""#_ftn1"">[1]</a> &nbsp; some opposition leaders mobilised their supporters and the Venezuelan Student Movement to protest against the government and call for its resignation – prominently <i>Leopoldo López</i>, leader of the centrist party Voluntad Popular (VP, Popular Will), <i>María Corina Machado</i> of the liberal party Vente Venezuela (Come Venezuela) and <i>Antonio Ledezma</i> of the social democratic party Alianza Bravo Pueblo (Fearless People's Alliance).<a title="" href=""#_ftn2"">[2]</a> It is sig <div><br clear=""all"" /> <hr align=""left"" size=""1"" width=""33%"" /> <div> <a title="" href=""#_ftnref1"">[1]</a> { ADDIN ZOTERO_ITEM CSL_CITATION {""citationID"":""klJTkj1B"",""properties"":{""formattedCitation"":""{\\rtf Vivia Sequera, \\uc0\\u8220{}Did Attempted Rape Ignite Venezuela\\uc0\\u8217{}s National Protests?,\\uc0\\u8221{} \\i Christian Science Monitor\\i0{}, February 22, 2014, http://www.csmonitor.com/World/Latest-News-Wires/2014/0222/Did-attempted-rape-ignite-Venezuela-s-national-protests.}"",""plainCitation"":""Vivia Sequera, “Did Attempted Rape Ignite Venezuela’s National Protests?,” Christian Science Monitor, February 22, 2014, http://www.csmonitor.com/World/Latest-News-Wires/2014/0222/Did-attempted-rape-ignite-Venezuela-s-national-protests.""},""citationItems"":[{""id"":1080,""uris"":[""http://zotero.org/groups/228165/items/U8EBSIQM""],""uri"":[""http://zotero.org/groups/228165/items/U8EBSIQM""],""itemData"":{""id"":1080,""type"":""article-magazine"",""title"":""Did attempted rape ignite Venezuela's national protests?"",""container-title"":""Christian Science Monitor"",""source"":""Christian Science Monitor"",""abstract"":""Student protests began at the University of the Andes in San Cristobal, Venezuela, after an attempted rape of a college woman. A week later, the protests boiled over into a violent national uprising."",""URL"":""http://www.csmonitor.com/World/Latest-News-Wires/2014/0222/Did-attempted-rape-ignite-Venezuela-s-national-protests"",""ISSN"":""0882-7729"",""author"":[{""family"":""Sequera"",""given"":""Vivia""}],""issued"":{""date-parts"":[[""2014"",2,22]]},""accessed"":{""date-parts"":[[""2014"",4,7]]}}}],""schema"":""https://github.com/citation-style-language/schema/raw/master/csl-citation.json""} } </div> <div> <a title="" href=""#_ftnref2"">[2]</a> { ADDIN ZOTERO_ITEM CSL_CITATION {""citationID"":""4YnaAzSw"",""properties"":{""formattedCitation"":""{\\rtf Sara Carolina D\\uc0\\u237{}az, \\uc0\\u8220{}Sector de La Oposici\\uc0\\u243{}n Convoca a Marcha Para El 12 de Febrero,\\uc0\\u8221{} February 2, 2014, http://www.eluniversal.com/nacional-y-politica/140202/sector-de-la-oposicion-convoca-a-marcha-para-el-12-de-febrero.}"",""plainCitation"":""Sara Carolina Díaz, “Sector de La Oposición Convoca a Marcha Para El 12 de Febrero,” February 2, 2014, http://www.eluniversal.com/nacional-y-politica/140202/sector-de-la-oposicion-convoca-a-marcha-para-el-12-de-febrero.""},""citationItems"":[{""id"":1136,""uris"":[""http://zotero.org/groups/228165/items/MTSN6T7J""],""uri"":[""http://zotero.org/groups/228165/items/MTSN6T7J""],""itemData"":{""id"":1136,""type"":""post-weblog"",""title"":""Sector de la oposición convoca a marcha para el 12 de febrero"",""abstract"":""Caracas.- Cientos de personas atendieron el llamado de parte de la dirigencia opositora y de Voluntad Popular en la plaza Brión de Chacaíto para participar en una asamblea popular con el fin de expresar su opinión sobre la salida posible a la crisis (...)"",""URL"":""http://www.eluniversal.com/nacional-y-politica/140202/sector-de-la-oposicion-convoca-a-marcha-para-el-12-de-febrero"",""author"":[{""family"":""Díaz"",""given"":""Sara Carolina""}],""issued"":{""date-parts"":[[""2014"",2,2]]},""accessed"":{""date-parts"":[[""2014"",4,7]]}}}],""schema"":""https://github.com/citation-style-language/schema/raw/master/csl-citation.json""} } </div> </div>"; Match m = Regex.Match(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