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

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^\[Error: +(?<source_path>(?<file>[^\s\n](?:[^\n:\\]+|\\.)+?)(?::(?<line>\d+)(?::(?<column>\d+)))?) *$"; string input = @"/usr/local/lib/node_modules/stylus/bin/stylus:685 throw err; ^ [Error: /Users/user/path/to/stylus/file/invalid.styl:34:5 30| ==/UserStyle== */ 31| 32| @-moz-document regexp(""https?://(www\\.)?typescriptlang.org/(v2/)?docs.*$""), 33| regexp(""https?://(www\\.)?(staging-)?typescript\\.org/docs/.*$"") 34| error(""compile error"") -----------^ 35| compile error ] { fromStylus: true, lineno: 34, column: 5, filename: '/Users/disk0/git.local/stylus-stylus/static/test/testFiles/invalid.styl', stylusStack: '', input: '/* ==UserStyle==\n' + '@name TypeScript Docs\n' + '@description Expands width of code blocks and moves navigation bar fully to the left\n' + '@version 0.0.12\n' + '@namespace github.com/disk0/stylus/typescript.org/docs\n' + '\n' + '@author disk0 (github.com/disco0)\n' + '@license MIT\n' + '\n' + '@preprocessor stylus\n' + '\n' + '@var select CodeFont ""Font for code displayed on page."" [\n' + ' ""Iosevka Extended*"",\n' + ' ""Iosevka Expanded"",\n' + ' ""Iosevka Term"",\n' + ' ""Iosevka"",\n' + '\n' + ' ""SemanticHaskell"",\n' + ' ""SemanticJavascript"",\n' + ' ""SemanticCode"",\n' + ' ""Hasklig"",\n' + '\n' + ' ""PragmataPro Mono Liga"",\n' + '\n' + ' ""monospace""\n' + ']\n' + '@var number CodeFontSize ""Size of code in documentation"" [ 14, 1, 500, 1, ""px"" ]\n' + '@var number CodeFontWeight ""Code font weight"" [ 400, 100, 900, 100 ]\n' + '@var number DocTextWidth ""Width of text content in documentation"" [ 1000, 300, 5000, 100, ""px"" ]\n' + '==/UserStyle== */\n' + '\n' + '@-moz-document regexp(""https?://(www\\\\.)?typescriptlang.org/(v2/)?docs.*$""),\n' + '\t regexp(""https?://(www\\\\.)?(staging-)?typescript\\\\.org/docs/.*$"")\n' + ' error(""compile error"")\n' } "; 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