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
Processing...

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"^pin ""([^""]*)"".* #.*@(\d+\.\d+\.\d+(?:[^\s]*)).*$"; string input = @"# Pin npm packages by running ./bin/importmap pin ""application"", preload: true pin ""@hotwired/turbo-rails"", to: ""turbo.min.js"", preload: true pin ""@hotwired/stimulus"", to: ""https://ga.jspm.io/npm:@hotwired/stimulus@3.0.1/dist/stimulus.js"" pin ""@hotwired/stimulus-loading"", to: ""stimulus-loading.js"", preload: true pin_all_from ""app/javascript/controllers"", under: ""controllers"" pin ""react"", to: ""https://ga.jspm.io/npm:react@16.0.0/index.js"" pin ""object-assign"" # @4.1.1 pin ""glob-parent"", to: ""https://ga.jspm.io/npm:glob-parent@3.1.0/index.js"" pin ""is-extglob"", to: ""https://ga.jspm.io/npm:is-extglob@2.1.1/index.js"" pin ""is-glob"", to: ""https://ga.jspm.io/npm:is-glob@3.1.0/index.js"" pin ""os"", to: ""https://ga.jspm.io/npm:@jspm/core@2.0.0-beta.18/nodelibs/browser/os.js"" pin ""path"", to: ""https://ga.jspm.io/npm:@jspm/core@2.0.0-beta.19/nodelibs/browser/path.js"" pin ""path-dirname"", to: ""https://ga.jspm.io/npm:path-dirname@1.0.2/index.js"" pin ""process"", to: ""https://ga.jspm.io/npm:@jspm/core@2.0.0-beta.19/nodelibs/browser/process-production.js"" pin ""util"", to: ""https://ga.jspm.io/npm:@jspm/core@2.0.0-beta.2/nodelibs/browser/util.js"" pin ""assastimulus"", to: ""https://ga.jspm.io/npm:stimulus@2.0.0/dist/stimulus.umd.js"" pin ""stimulus"", to: ""https://ga.jspm.io/npm:stimulus@2.0.0/dist/stimulus.umd.js"" pin ""lodash"" # @4.17.1 a comment pin ""@github/hotkey"", to: ""@github--hotkey.js"" # @2.0.0 pin ""is-svg"", to: ""https://ga.jspm.io/npm:is-svg@3.0.0/index.js"" pin ""buffer"", to: ""https://ga.jspm.io/npm:@jspm/core@2.0.0-beta.19/nodelibs/browser/buffer.js"" pin ""html-comment-regex"", to: ""https://ga.jspm.io/npm:html-comment-regex@1.1.2/index.js"" pin ""nth-check"", to: ""https://ga.jspm.io/npm:nth-check@1.0.0/index.js"" pin ""boolbase"", to: ""https://ga.jspm.io/npm:boolbase@1.0.0/index.js"" pin ""jquery"", to: ""https://cdn.jsdelivr.net/npm/jquery@3.6.0/dist/jquery.js"" pin ""angularjs"", to: ""https://unpkg.com/angularjs@0.0.1/index.js"" pin ""angular"", to: ""https://unpkg.com/angular@1.8.2/index.js"" pin ""@angular/cli"", to: ""https://unpkg.com/@angular/cli@13.2.5/lib/cli/index.js"" pin ""underscore"" # a comment @1.13.2 "; 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