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

@
@
gmis

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"class=""[^""]*(?<=""|\s)left-top-container(?=""|\s)[^""]*""[^<]*<h2[^>]*>(?<title>[^<]*)</h2"; string input = @"<div class=""left-top-container""> <h2 itemprop=""name""> Nike Magista</h2> <div class=""listing_info""> <div class=""list_id""><strong>List-ID: </strong>52002304 </div> <div class=""list_time""> Yesterday 09:20 </div> </div> <div class=""ad_images""> <!-- IMAGE GALLERY --> <div class="" id=""image-gallery""> <div id=""gallery-image-border""> <meta itemprop=""image"" content=""http://img.rnudah.com/images/04/044707022491864.jpg""> <span class=""trackable favourite-heart favourite-heart-empty"" aria-hidden=""true"" data-list-id=""52002304"" data-company-ad=""0"" data-category=""4160"" data-region=""7"" data-event_type=""view"" data-event_name=""save_favourite_ad"" data-page_name=""Add Favourite Ad"" data-xtn2=""5"" data-xiti_f1=""4160"" data-xiti_f2=""7"" data-xiti_f3=""2"" data-xiti_f4=""2"" data-xiti_f5=""248""></span> <div class=""heart-icon-tip adview-tip""> <div class=""arrow-tip""></div> <div class=""tip-content""> Click on the heart to add this to your Favourite list. </div> </div> <div id=""gallery-image-container""><span><a href=""javascript:void(0)"" onclick=""gallery.nextImage()""><img src=""http://img.rnudah.com/images/04/044707022491864.jpg"" style=""margin-top:44px;margin-left:0px""></a></span></div> </div> </div> <div id=""gallery-thumbnail-containers"" style=""display: none""> <ul id=""gallery-thumbnail-items""> <li><a href=""javascript:void(0)"" onclick=""gallery.move('prev')"" class=""gallery-navigation"" style=""display: none;""><img src=""/img/none.gif"" class=""sprite_view_arrow-left""></a></li> <li id=""gallery-thumbnails-li""> <div id=""gallery-thumbnails-ul-container""> <ul id=""gallery-thumbnails"" style=""width: 540px;""><li data-sort=""1"" class=""thumbnail-active""><a href=""javascript:void(0)"" style=""margin-top: 5.5px"" onmouseover=""gallery.changeGalleryImage(&quot;0&quot;)""><img src=""http://img.rnudah.com/thumbs/04/044707022491864.jpg""></a></li></ul> </div> </li> <li><a href=""javascript:void(0)"" onclick=""gallery.move('next')"" class=""gallery-navigation"" style=""display: none;""><img src=""/img/none.gif"" class=""sprite_view_arrow-right""></a></li> </ul> </div> <!-- IMAGE GALLERY --> </div> <div class=""ad_info""> </div></div>"; RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase | RegexOptions.Singleline; 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