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

/
/
gmx

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?=""_id""\s*:)(?&key_value) (?(DEFINE) (?<string_inner>(?<=[""])(?>[^""\\]++|[\\].)++(?=[""])) (?<string>[""](?&string_inner)?+[""]) (?<object>[{]\s*+(?&key_values)?+\s*+[}]) (?<array>\[\s*+(?&values)?+\s*+\]) (?<key_values>(?&key_value)(?>\s*+[,]\s*+(?&key_value))*+) (?<key_value>(?&string)\s*+[:]\s*+(?&value)) (?<number>[-]?+\d++(?>[.]\d++)?+(?>[Ee][+-]?+\d++)?+) (?<bool>true|false) (?<scalar>(?&bool)|(?&number)|(?&string)|null) (?<value>(?&scalar)|(?&object)|(?&array)) (?<values>(?&value)(?>\s*+[,]\s*+(?&value))*+) )"; string input = @"[ { ""_id"": ""56af331efbeca6240c61b2ca"", ""index"": 120000, ""guid"": ""bedb2018-c017-429E-b520-696ea3666692"", ""isActive"": false, ""balance"": ""$2,202,350"", ""object"": { ""name"": ""alexander"", ""lastname"": ""lang"" } } ] "; RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnorePatternWhitespace; 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