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 = @"(?=[""'])""([^""\\\n]*(?:\\[\s\S][^""\\\n]*)*)["",.!]|'([^'\\\n]*(?:\\[\s\S][^'\\\n]*)*)[',.!]"; string input = @"""Then"", he said, ""we go home."" ""My dear Lizzy, ""I wish you joy. If you love Mr. Darcy half as well as I do my dear Wickham, you must be very happy. It is a great comfort to have you so rich, and when you have nothing else to do, I hope you will think of us. I am sure Wickham would like a place at court very much, and I do not think we shall have quite money enough to live upon without some help. Any place would do, of about three or four hundred a year; but however, do not speak to Mr. Darcy about it, if you had rather not. ""Yours, etc."" ""Hello World"" ""Hey!Theererererzffzfzfzfz zfzfbcnhdzxghxhxhxhx"" Hello World!I am ""Some random text"" ""Hey There! This is Some Text!!!! which does not contain quotes. ""thefbjbbssbjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjcbsjcb cbcslablaffblafblbflabflbfabfalafbalbabfaflaflzbzbhavsjdjdbeblbvsbvskbv"" 'Hello!!! This is single quoted example.' 'Hello!!!' This is single quoted example.'Here is the one. "; 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