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

/
/
is

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<a href=""javascript:void\(0\)""[^>]*>(.*?)id=""sw-slots-grid-line-break"""; string input = @"<div id=""tmm-grid-swatch-HARDCOVER"" class=""a-column a-span6 a-text-left swatchElement selected celwidget"" role=""listitem"" data-csa-c-id=""rqzqyx-arj8qg-jifnrc-pelgtz"" data-cel-widget=""tmm-grid-swatch-HARDCOVER""> <span class=""a-button a-button-selected a-spacing-none a-button-toggle format"" id=""a-autoid-2""><span class=""a-button-inner""><a href=""javascript:void(0)"" role=""radio"" aria-checked=""true"" aria-current=""page"" class=""a-button-text a-text-left"" id=""a-autoid-2-announce""> <span class=""slot-title""> <span aria-label=""Hardcover Format:"">Hardcover</span> <br> </span> <span class=""slot-price""> <span aria-label=""$16.94"" class=""a-size-base a-color-price a-color-price""> $16.94 </span> </span> <br id=""sw-slots-grid-line-break""> </a></span></span> </div>"; RegexOptions options = RegexOptions.IgnoreCase | RegexOptions.Singleline; Match m = Regex.Match(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