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 = @"Json(?<json_output>[\s\S\d\D\w\W]*)"; string input = @"```json [ { ""Place"": { ""Name"": ""Les Catacombes de Paris"", ""Google_place_id"": ""ChIJVXealLU_xkcRja_At0z9AGY"", ""City"": ""Paris"", ""Region"": ""Île-de-France"", ""Country"": ""France"", ""Cultural_type"": ""Historical"", ""Facts"": { ""Historical_facts"": { ""FACT_TYPE"": ""Did you know ?"", ""FACTS"": [ ""Les Catacombes de Paris ont été créées à la fin du 18ème siècle pour résoudre le problème de surpeuplement des cimetières de la ville."" ], ""INTERACTION"": [ ""Savez-vous pourquoi les catacombes ont été construites ?"" ], ""CATEGORY"": ""Historical_facts"" }, ""Architectural_facts"": { ""FACT_TYPE"": ""Fun fact"", ""FACTS"": [ ""Les catacombes sont faites d’anciens tunnels de carrières transformés pour stocker les ossements de plus de six millions de Parisiens."" ], ""INTERACTION"": [ ""Combien de personnes pensez-vous que les catacombes peuvent contenir ?"" ], ""CATEGORY"": ""Architectural_facts"" }, ""Scientific_facts"": { ""FACT_TYPE"": ""Wow"", ""FACTS"": [ ""Les conditions dans les catacombes, qui sont fraîches et humides, permettent une bonne conservation des ossements."" ], ""INTERACTION"": [ ""Que pensez-vous que l'humidité fait aux ossements ?"" ], ""CATEGORY"": ""Scientific_facts"" }, ""Mystery_legends_facts"": { ""FACT_TYPE"": ""Did you know ?"", ""FACTS"": [ ""Une légende urbaine raconte qu’il y a un cinéma secret dans les catacombes !"", ""Il paraîtrait que des groupes se réunissent ici pour regarder des films."" ], ""INTERACTION"": [ ""Aimeriez-vous visiter un cinéma caché ?"", ""Quel genre de film pensez-vous qu’ils projettent là-bas ?"" ], ""CATEGORY"": ""Mystery_legends_facts"" } } } } ] ```"; 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