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 = @"<a[^>]*?href=([""\'])?((?:.(?!\1|>))*.?)\1?"; string input = @"<li class=""navItem ""><a href=""/services/"" lang=""de"" hreflang=""de"">Services</a></li> <a class=""iMacLink"" href=""/portfolio/"" ><div class=""iMacOverlay""></div><div class="">Super</div></a></div> <div class=""addthis_toolbox addthis_default_style""> <a itemprop=""url"" target=""_blank"" href=""https://www.facebook.com/any-profile"" title=""facebook"" class=""facebookSite""><span class=""icon-facebook""></span></a> <a itemprop=""url"" target=""_blank"" href=""https://twitter.com/any-profile"" title=""twitter"" class=""twitterSite""><span class=""icon-twitter""></span></a> <a itemprop=""url"" target=""_blank"" href=""https://pinterest.com/any-profile"" title=""pinterest"" class=""pinterestSite""><span class=""icon-pinterest""></span></a> <a itemprop=""url"" target=""_blank"" href=""//feeds.feedburner.comany-profile?format=xml"" title=""rss"" class=""rss""><span class=""icon-rss""></span></a> </div> <a class=""social facebookProfil"" href=""http://www.facebook.com/any-profile"">Facebook</a> <a class=""social facebookProfil"" href='https://www.facebook.com/single-quotes'>Facebook</a> <a class=""social facebookProfil"" href=https://www.facebook.com/no-quotes>Facebook</a> <a class=""social youtubeProfil"" href=""http://www.youtube.com/user/any-profile"">Youtube</a> <a class=""social vimeoProfil"" href=""http://vimeo.com/any-profile"">Vimeo</a> <a class=""social xingProfil"" href=""https://www.xing.com/companies/any-profile"">XING</a> <a class=""social twitterProfil"" href=""https://twitter.com/any-profile"">Folge bei Twitter</a> <a href=""https://www.instagram.com/p/CN-Kx40nOW0/"">Instagram Beitrag</a> <a href=""http://instagram.com/quellenhofaachen"">Instagram Profil</a> <a href=""https://www.instagram.com/explore/tags/url"">Instagram Tag-Url</a> <A href=""https://www.Instagram.com/uppercase-link"">Upercase-link</A> <a href=""http://instagram.com/unique"">Unique-test http</a> <a href=""//instagram.com/unique"">Unique-test protocol relative</a> <a href=""https://instagram.com/unique"">Unique-test https</a> <a href=""http://www.instagram.com/unique"">Unique-test www</a> "; 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