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

/
/
gx

Test String

Code Generator

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"(?(DEFINE) (?<recurs> (?! {@|@} ) [^|] [^{@|\\]* ( \\.[^{@|\\]* )* | (?R) ) ) {@ (?<If>\w+)- (?<Condition>(%?\w++ (:\w+)*)* ) (?<True> [|] [^{@|]*+ (?&recurs)* ) (?<False> [|] (?&recurs)* )? \s*@}"; string input = @"{@if-statement:sub%statement2| <header id=""header_home""> <div class=""in""> <div class=""top""> <h1 class=""logo""><a href=""/""><img src=""/img/logo-home.png"" alt=""></a></h1> <div class=""login_outer_wrapper""> <button id=""login""><div class=""a""><i class=""stripe""><i></i></i>Log in</div></button> <div id=""login_wrapper""> <form method=""post"" action=""{^login^}"" id=""form_login_global""> <div class=""form_field no_description""> <label>{!auth:login_email!}</label> <div class=""input""><input type=""text"" name=""form[login]""></div> </div> <div class=""form_field no_description password""> <label>{!auth:password!}</label> <div class=""input""><input type=""password"" name=""form[password]""></div> </div> <div class=""remember""> <input type=""checkbox"" name=""remember"" id=""remember_me_check"" checked> <label for=""remember_me_check""><i class=""fa fa-check"" aria-hidden=""true""></i>Remember</label> </div> <div class=""submit_box""> <button class=""btn btn_check"">Log in</button> </div> </form> </div> </div> </div> <div class=""content clr""> <div class=""main_menu""> <a href=""> <i class=""ico a""><i class=""fa fa-lightbulb-o"" aria-hidden=""true""></i></i> <span>Idea</span> <div>&nbsp;</div> </a> <a href=""> <i class=""ico b""><i class=""fa fa-user"" aria-hidden=""true""></i></i> <span>FFa</span> </a> <a href=""> <i class=""ico c""><i class=""fa fa-briefcase"" aria-hidden=""true""></i></i> <span>Buss</span> </a> </div> <div class=""text_wrapper""> <div> <div class=""register_wrapper""> <a id=""main_register"" class=""btn register"">Załóż konto</a> <form method=""post"" action=""{^login^}"" id=""form_register_home""> <div class=""form_field no_description""> <label>{!auth:email!}</label> <div class=""input""><input type=""text"" name=""form2[email]""></div> </div> <div class=""form_field no_description password""> <label>{!auth:password!}</label> <div class=""input tooltip""><input type=""password"" name=""form2[password]""><i class=""fa fa-info-circle tooltip_open"" aria-hidden=""true"" title=""{!auth:password_format!}""></i></div> </div> <div class=""form_field terms no_description""> <div class=""input""> <input type=""checkbox"" name=""form2[terms]"" id=""terms_check""> <label for=""terms_check""><i class=""fa fa-check"" aria-hidden=""true""></i>Agree</label> </div> </div> <div class=""form_field no_description""> <div cl\|\|ass=""input captcha_wrapper""> <div class=""g-recaptcha"" data-sitekey=""{%captcha_public_key%}""></div> </div> </div> <div class=""submit_box""> <button class=""btn btn_check"">{!auth:register_btn!}</button> </div> </form> </div> </div> </div> </div> </div> </header>|{@if-statement2|echo this|{@if-statement2|echo this|echo othe\|\|rwise@}@} @}"; RegexOptions options = RegexOptions.IgnorePatternWhitespace; 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