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 = @"(?si)\A\s*(?:(<!--.*?-->|<!DOCTYPE\s+svg([\s:]+.*?>|>))\s*)*<svg[\s>\/]"; string input = @"<!-- test --> some <p></p> html tags, this svg file is not valid also, look after </svg> ends <!-- prettier-ignore --> <svg xmlns=""http://www.w3.org/2000/svg"" width=""10"" height=""10"" viewBox=""0 0 10 10""> <path fill=""#8E8E93"" fill-rule=""evenodd"" d=""M9.816 8.981L7.08 6.243c.49-.67.753-1.479.75-2.309C7.819 1.767 6.067.013 3.9 0 2.864-.005 1.868.406 1.135 1.14.403 1.872-.006 2.868 0 3.905.01 6.072 1.762 7.828 3.93 7.84c.833.004 1.645-.262 2.315-.758l.003-.002 2.735 2.736c.148.156.368.218.576.165.207-.054.37-.216.423-.424.054-.207-.01-.428-.165-.576zm-5.89-1.925C2.193 7.046.79 5.642.783 3.909c-.005-.83.322-1.626.908-2.213.586-.587 1.383-.915 2.212-.912 1.733.01 3.135 1.414 3.143 3.147.004.83-.323 1.626-.909 2.213-.586.587-1.382.915-2.211.912z""/> </svg> <svg xmlns=""http://www.w3.org/2000/svg"" width=""10"" height=""10"" viewBox=""0 0 10 10""><path fill=""#8E8E93"" fill-rule=""evenodd"" d=""M9.816 8.981L7.08 6.243c.49-.67.753-1.479.75-2.309C7.819 1.767 6.067.013 3.9 0 2.864-.005 1.868.406 1.135 1.14.403 1.872-.006 2.868 0 3.905.01 6.072 1.762 7.828 3.93 7.84c.833.004 1.645-.262 2.315-.758l.003-.002 2.735 2.736c.148.156.368.218.576.165.207-.054.37-.216.423-.424.054-.207-.01-.428-.165-.576zm-5.89-1.925C2.193 7.046.79 5.642.783 3.909c-.005-.83.322-1.626.908-2.213.586-.587 1.383-.915 2.212-.912 1.733.01 3.135 1.414 3.143 3.147.004.83-.323 1.626-.909 2.213-.586.587-1.382.915-2.211.912z""/></svg> </div> <button class=""product-list-filter__reset"" type=""button""> @ -49,9 +50,10 @@ <div class=""product-list-filter__scrollable""> <div class=""js-namings-autocomplete-matched""> @foreach ($filter_namings->sortBy('display_name') as $naming) @continue($search_namings->contains('display_name', $naming->display_name)) <div class=""spoiler__item""> <label tabindex=""0""> <input type=""checkbox"" value=""{{ $naming->id }}"" {{ $search_namings->contains($naming->display_name) ? 'data-checked=""true""' : 'data-checked=""false""' }}> <input type=""checkbox"" value=""{{ $naming->id }}"" {!! $search_namings->contains('display_name', $naming->display_name) ? 'data-checked=""true""' : 'data-checked=""false""' !!}> <span>{{ $naming->display_name }}</span> </label> </div>"; 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