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

/
/
gi

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(\[(?<first>icode|quote|code)[^\]]*?\](?:[\s]*?.)*?[\s]*?\[\/(?:\k<first>)\])"; string input = @"[quote]Id in voluptatem [U]odit itaque[/U] ea. Qui eum [URL='http://#']fugiat[/URL] doloribus dicta nisi. [icode]Exercitationem sit error maxime aperiam quaerat hic deleniti quidem[/icode]. Totam laudantium aut quia. ""Sint ut ut vel ratione,"" Qui porro eaque enim fugit. [/quote] Quam consequatur consequatur voluptate molestiae explicabo [icode]qui consectetur[/ICODE], ""Voluptatem saepe [b]ex adipisci aut est rem[/b]."" Numquam a cupiditate non officiis sed aspernatur. [quote=""Lorem Ipsum, post: 12345, member: 123""]Aut deleniti nihil sit. Saepe dolorem blanditiis nemo. Ab et cumque nesciunt. Quos velit vel nam porro.[/quote] [spoiler=""Name""]Unde et eius tempore consequatur. ""Vitae est ut et,"" est numquam.""[/spoiler] Quo <span style=""color: #24c4f9""><b>suscipit</b></span> sequi id ratione ""doloribus omnis"". <span style=""font-family: 'Lucida Console'""><span style=""font-size: 18px"">Lorem ipsum dolor sit amet, consectetur adipiscing elit. "" Maecenas sed nibh ac neque semper finibus. Saepe dolorem blanditiis nemo. "" </b></span> [CODE=html] Vivamus hendrerit augue ""volutpat"", consequat risus sed, dignissim orci. Fusce sed pellentesque ipsum. Suspendisse nisi odio, gravida sed leo ut, tristique posuere felis. [/CODE] Ut tempor vestibulum viverra. Vivamus imperdiet fringilla est fermentum facilisis. Quisque nec massa sit amet augue eleifend condimentum at nec arcu. [CENTER][B]Quam consequa[/B] ""tur c[I]onse[/I]quatur"". Eum molestias ""et"" doloribus et rem dolorem vero qui.[/CENTER]"; RegexOptions options = RegexOptions.IgnoreCase; 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