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

/
/
mg

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<figure[^>]*>([\t\n\r\s]*)<figcaption[^>]*>(.*)<\/figcaption>([\t\n\r\s]*)<audio[^>]*>(([\t\n\r\s]|.)*)<\/audio>([\t\n\r\s]*)<\/figure>"; string substitution = @""; string input = @"<!-- Une simple image --> <figure> <img src=""https://developer.mozilla.org/static/img/favicon144.png"" alt=""Le logo de MDN.""> </figure> <!-- Une image avec une légende --> <figure> <img src=""https://developer.mozilla.org/static/img/favicon144.png"" alt=""Le logo de MDN.""> <figcaption>Logo MDN</figcaption> </figure> <figure> <figcaption>Obtenir les détails du navigateur</figcaption> <pre> function NavigatorExample(){ let txt; txt = ""Nom de code: "" + navigator.appCodeName; txt += ""Nom du navigateur : "" + navigator.appName; txt += ""Version : "" + navigator.appVersion ; txt += ""Cookies activés : "" + navigator.cookieEnabled; txt += ""Plate-forme: "" + navigator.platform; txt += ""En-tête d'agent utilisateur : "" + navigator.userAgent; console.log(""NavigatorExample"", txt); } </pre> </figure> <figure> <figcaption> <cite>Edsger Dijkstra : </cite> </figcaption> <p>« Si le débogage correspond au retrait de bogues, alors la programmation correspond à l'ajout de bogues. » </p> </figure> <figure style=""display:table; margin:0 auto;""> <img loading=""lazy"" src=""/public/illustrations/2021/.grole_u.jpg"" alt=""Grole abandonnée sur les rochers, août 2021"" title=""Grole abandonnée sur les rochers, août 2021"" height=""600"" width=""600"" class=""a42-ac-replace-img""> <figcaption>Grole abandonnée sur les rochers du petit port de Pen-Hors</figcaption> </figure> <figure style=""display:table; margin:0 auto;""> <a href=""#""> <img loading=""lazy"" src=""/public/illustrations/2021/.grole_u.jpg"" alt=""Grole abandonnée sur les rochers, août 2021"" title=""Grole abandonnée sur les rochers, août 2021"" height=""600"" width=""600"" class=""a42-ac-replace-img""> </a> <figcaption>Grole abandonnée sur les rochers du petit port de Pen-Hors</figcaption> </figure> <figure style=""display:table; margin:0 auto;""><a href=""#""><img loading=""lazy"" src=""/public/illustrations/2021/.grole_u.jpg"" alt=""Grole abandonnée sur les rochers, août 2021"" title=""Grole abandonnée sur les rochers, août 2021"" height=""600"" width=""600"" class=""a42-ac-replace-img""></a><figcaption>Grole abandonnée sur les rochers du petit port de Pen-Hors</figcaption></figure> <figure> <figcaption>Listen to the T-Rex:</figcaption> <audio controls src=""/media/cc0-audio/t-rex-roar.mp3""> Your browser does not support the <code>audio</code> element. </audio> </figure> "; RegexOptions options = RegexOptions.Multiline; Regex regex = new Regex(pattern, options); string result = regex.Replace(input, substitution); } }

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