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 = @"(href|src|source|retinaSource|data)=([""|'][^""']*assets[^""']*\.\w{1,5})(\?[^""']*)?[""|']"; string input = @"<a href=""javascript://"" class=""btn btn-continue-operation disabled""> <span>Continuar</span> </a> <a href='javascript://"" class=""btn btn-continue-operation disabled'> <span>Continuar</span> </a> <ul class=""footer-legal l-adjacent-list""> <li><a href=""#external-content//genoma_transactional/cms_files/corporativo/seguridad-internet/index_transaccional.html"" class=""footer-legal-element clr-gray.html"">{security}</a></li> <li><a href='#external-content//genoma_transactional/cms_files/corporativo/sobre-ing/condiciones-servicio-tarifa_transaccional.html' class=""footer-legal-element clr-gray"">{link-legal-info-footer}</a></li> </ul> <link type=""text/css"" href="" assets/custom-css /infobolsa .css"" rel=""stylesheet"" media=""all"" charset=""utf-8""> <div class=""fingerprint-views-storage-content-img txt-c""> {>pp-image imageId=""fingerprint-activation"" altText=""fingerprint-activation"" source=""assets/images/fingerprint-activation.png"" retinaSource=""assets/images/retina/fingerprint-activation@2x.png""/} </div> <img src=""modules/cc-menu/assets/images/logo_cc.svg"" alt=""Components catalog""> <img src=""assets/images/twyp_cash_circle.svg?query=34""> <img src=""assets/ircle.svg?hgt=76""> {>pp-image imageId=""budgets-tutorial-client-step3"" altText=""budget-tutorial-step3"" source=""components/budgets-tutorial/ASSETS/images/budgets-tutorial-client-step3.png"" {>pp-image imageId=""budgets-tutorial-client-step3"" altText=""budget-tutorial-step3"" source=""components/budgets-tutorial/ASSETS/images/budgets-tutorial-client-step3.png"" {>pp-image source=""assets/images/svg/logoING.svg""/} <div data-selector=""logo-ing"" class=""padding-top-sm padding-left-sm pull-left""> <img id=""logo"" src=""assets/images/svg/logoING.svg"" class=""img-svg svg-header-logo login-header""> </div> <audio data-selector=""customer-connected-audio""> <source src=""modules/remote-advisor-agent/assets/audio/incomingCall.mp3"" type=""audio/mp3""/> </audio> <div class=""col9""> <div class=""declaration-image-div"">{>pp-svg-image:no-products-other-bank imageId=""declaration-image"" source=""./assets/images/life-insurance-contract/cuestionario_riesgos.svg""/}</div> <p class=""h5 clr-dark-gray lic-declaration-remark"">{lic-risk-declaration-remark|s}</p> </div> <div data-region-id=""login-dnie-image"" class=""login-dnie-image""><img src=""assets/images/dni-logo.png""/></div>"; 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