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 = @"<a.*<\/a>"; string input = @"<dl> <dd>[1] <a href=""/wiki/Geb%C3%A4ude"" title=""Gebäude"">Gebäude</a>, <a href=""/wiki/R%C3%A4umlichkeit"" title=""Räumlichkeit"">Räumlichkeit</a>, <a href=""/wiki/Unterkunft"" title=""Unterkunft"">Unterkunft</a> </dd> <dd>[2] die <a href=""/wiki/Gemeinschaft"" title=""Gemeinschaft"">Gemeinschaft</a> der <a href=""/wiki/Mensch"" title=""Mensch"">Menschen</a>, die unter einem Dach zusammen leben, wohnen oder arbeiten</dd> <dd>[3] der <a href=""/wiki/Unterhaltung"" title=""Unterhaltung"">Unterhaltung</a> dienendes Gebäude</dd> <dd>[4] <i><a href=""/wiki/Astrologie"" title=""Astrologie"">Astrologie</a>:</i> <a href=""/wiki/Tierkreiszeichen"" title=""Tierkreiszeichen"">Tierkreiszeichen</a> </dd> <dd>[5] <a href=""/w/index.php?title=Herrscherhaus&amp;action=edit&amp;redlink=1"" class=""new"" title=""Herrscherhaus (Seite nicht vorhanden)"">Herrscherhaus</a> </dd> <dd>[6] <a href=""/wiki/Firma"" title=""Firma"">Firma</a>, <a href=""/wiki/Unternehmen"" title=""Unternehmen"">Unternehmen</a> </dd> <dd>[7] <a href=""/wiki/scherzhaft"" title=""scherzhaft""><i>scherzhaft</i></a> <a href=""/wiki/Freund"" title=""Freund"">Freund</a> </dd> <dd>[8] <i><a href=""/wiki/umgangssprachlich"" title=""umgangssprachlich"">umgangssprachlich</a>:</i> Gehäuse der <a href=""/wiki/Schnecke"" title=""Schnecke"">Schnecke</a> </dd> <dd>[9] Gasthaus oder <a href=""/wiki/Gastst%C3%A4tte"" title=""Gaststätte"">Gaststätte</a> </dd> </dl> "; 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