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

/
/
gm

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(\s*\{(?:\s*""Modulus""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(3)(?(4)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*""Exponent""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(2)(?(4)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*""P""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(2)(?(3)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*""Q""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(2)(?(3)(?(4)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*""DP""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(2)(?(3)(?(4)(?(5)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*""DQ""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(2)(?(3)(?(4)(?(5)(?(6)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*""InverseQ""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(2)(?(3)(?(4)(?(5)(?(6)(?(7)(?(9)|,)|,)|,)|,)|,)|,)|,)()|\s*""D""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(2)(?(3)(?(4)(?(5)(?(6)(?(7)(?(8)|,)|,)|,)|,)|,)|,)|,)()){8}\s*\}\s*\2\3\4\5\6\7\8\9)|(\s*\{(?:\s*""Modulus""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(12)|,)()|\s*""Exponent""\s*:\s*""[a-zA-Z\d\+\/]+={0,2}""\s*(?(11)|,)()){2}\s*\}\s*\11\12)"; string input = @" { ""Modulus"": ""AQAB"", ""Exponent"": ""AQAB"", ""P"": ""AQAB"", ""Q"": ""AQAB"", ""DP"": ""AQAB"", ""DQ"": ""AQAB"", ""InverseQ"": ""AQAB"", ""D"": ""AQAB"" } { ""Modulus"": ""AQAB"", ""Exponent"": ""AQAB"" } (?(1)(?(2)(?(3)(?(4)(?(5)(?(6)(?(7)|,)|,)|,)|,)|,)|,)|,) 2-3-4-5-6-7-8-9 (?(3)(?(4)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(4)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(5)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(6)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(5)(?(7)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(5)(?(6)(?(8)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(5)(?(6)(?(7)(?(9)|,)|,)|,)|,)|,)|,)|,) (?(2)(?(3)(?(4)(?(5)(?(6)(?(7)(?(8)|,)|,)|,)|,)|,)|,)|,) (?(DEFINE)(?P<b64>[a-zA-Z\d\+\/]+={0,2})(?P<Q1>\s*"")(?P<C1>(?(22)(?(23)(?(24)(?(25)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C2>(?(21)(?(23)(?(24)(?(25)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C3>(?(21)(?(22)(?(24)(?(25)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C4>(?(21)(?(22)(?(23)(?(25)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C5>(?(21)(?(22)(?(23)(?(24)(?(26)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C6>(?(21)(?(22)(?(23)(?(24)(?(25)(?(27)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C7>(?(21)(?(22)(?(23)(?(24)(?(25)(?(26)(?(28)|,)|,)|,)|,)|,)|,)|,))(?P<C8>(?(21)(?(22)(?(23)(?(24)(?(25)(?(26)(?(27)|,)|,)|,)|,)|,)|,)|,))(?P<Q2>""\s*:\s*""(?P>b64)""\s*)(?P<Modulus>(?P>Q1)Modulus(?P>Q2))(?P<Exponent>(?P>Q1)Exponent(?P>Q2))(?P<P>(?P>Q1)P(?P>Q2))(?P<Q>(?P>Q1)Q(?P>Q2))(?P<DP>(?P>Q1)DP(?P>Q2))(?P<DQ>(?P>Q1)DQ(?P>Q2))(?P<InverseQ>(?P>Q1)InverseQ(?P>Q2))(?P<D>(?P>Q1)D(?P>Q2)))(\s*{\s*)(?:(?P>Modulus)(?P>C1)()|(?P>Exponent)(?P>C2)()|(?P>P)(?P>C3)()|(?P>Q)(?P>C4)()|(?P>DP)(?P>C5)()|(?P>DQ)(?P>C6)()|(?P>InverseQ)(?P>C7)()|(?P>D)(?P>C8)()){8}\s*}"; 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