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

`
`
gmX

Test String

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"<td.*?class=""namelinks"".*?"">(.+?)</a>"; string input = @"<tr> <td class=""field_domain""><a href=""/goto/1/eboo74/2/"" target=""_blank"" title=""advocaciamdc.com"" class=""namelinks"" id=""linksdd-domaineboo74"">advocaciamdc.com</a><ul id=""links-domaineboo74"" class=""kmenucontent"" style=""display:none;""><li class=""first""><a href=""/goto/16/eg4d59/2/"" target=""_blank"" class=""favicons favgodaddy"" title=""Register at GoDaddy.com"">GoDaddy.com</a></li><li><a href=""/goto/53/ee87fh/2/"" target=""_blank"" class=""favicons favdynadot"" title=""Register at Dynadot.com"">Dynadot.com</a></li><li><a href=""/goto/43/eecp19/2/"" target=""_blank"" class=""favicons favnamecheap"" title=""Register at Namecheap.com"">Namecheap.com</a></li></ul></td> <td class=""field_watchlist""><span class=""wl"" id=""wl-2-eboo74""></span></td> <td class=""field_length"">12</td> <td class=""field_bl""><a href=""/goto/34/ebdukr/2/"" target=""_blank"" class=""bllinks"" title=""0"" id=""backlinks-bleboo74"">0</a><ul id=""links-bleboo74"" class=""kmenucontent"" style=""display:none;""><li class=""first""><a href=""/goto/34/ebdukr/2/"" target=""_blank"" class=""favicons favmajestic"" title=""Check Backlinks on Majestic.com"">Majestic.com</a></li><li class=""seperator"">&nbsp;</li><li><a href=""/goto/28/eg64b8/2/"" target=""_blank"" class=""favicons favseokicks"" title=""Check Backlinks on SEOkicks.de"">SEOkicks.de</a></li><li><a href=""/goto/56/ed1td8/2/"" target=""_blank"" class=""favicons favsemrush"" title=""Check Backlinks on SEMRush.com"">SEMRush.com</a></li><li><a href=""/goto/27/ecwtfo/2/"" target=""_blank"" class=""favicons favsearchm"" title=""Searchmetrics"">Searchmetrics</a></li></ul></td> <td class=""field_domainpop""><a href=""/goto/28/eg64b8/2/"" target=""_blank"" title=""0"">0</a></td> <td class=""field_creationdate""><a href=""/goto/8/edemrz/2/"" target=""_blank"" title=""Whois Creation Date: 2019-08-06"">2019</a></td> <td class=""field_abirth"">-</td> <td class=""field_aentries""><a href=""/goto/6/eddzzf/2/"" target=""_blank"" title=""0 saved crawl results"">0</a></td> <td class=""field_alexa""><a href=""/goto/4/eddwsg/2/"" target=""_blank"" title=""0"" class="">0</a></td> <td class=""field_majestic_globalrank""><a href=""/goto/34/ebdukr/2/"" target=""_blank"">0</a></td> <td class=""field_dmoz"">-</td> <td class=""field_statustld_registered""><a href=""/domain/advocaciamdc.com#namestatus"" target=""_blank"">0</a></td> <td class=""field_statuscom""><a href=""/goto/18/efli0j/2/?tld=com"" target=""_blank"" class=""sprite stlds stld22c"" title="".com available""><span>available</span></a></td> <td class=""field_statusnet""><a href=""/goto/18/efli0j/2/?tld=net"" target=""_blank"" class=""sprite stlds stld22c"" title="".net available""><span>available</span></a></td> <td class=""field_statusorg""><a href=""/goto/18/efli0j/2/?tld=org"" target=""_blank"" class=""sprite stlds stld22c"" title="".org available""><span>available</span></a></td> <td class=""field_statusbiz""><a href=""/goto/18/efli0j/2/?tld=biz"" target=""_blank"" class=""sprite stlds stld22c"" title="".biz available""><span>available</span></a></td> <td class=""field_statusinfo""><a href=""/goto/18/efli0j/2/?tld=info"" target=""_blank"" class=""sprite stlds stld22c"" title="".info available""><span>available</span></a></td> <td class=""field_statusde""><a href=""/goto/18/efli0j/2/?tld=de"" target=""_blank"" class=""sprite stlds stld22c"" title="".de available""><span>available</span></a></td> <td class=""field_adddate"">2020-10-25</td> <td class=""field_related_cnobi"">-</td> <td class=""field_wikipedia_links"">-</td> <td class=""field_changes"">Yesterday 18:55</td> <td class=""field_whois""><a href=""/goto/1/eboo74/2/"" target=""_blank"" title=""Register now"" class=""status_free"">available</a></td> <td class=""field_relatedlinks""><a class=""sprite sicon smenu domainlinks"" href=""#"" id=""expiredcom-eboo74"" title=""Related Links (click here for menu)""><span>RL</span></a><ul id=""links-eboo74"" class=""kmenucontent"" style=""display:none;""><li class=""first""><a href=""/goto/16/eg4d59/2/"" target=""_blank"" class=""favicons favgodaddy"" title=""Register at GoDaddy.com"">GoDaddy.com</a></li><li><a href=""/goto/53/ee87fh/2/"" target=""_blank"" class=""favicons favdynadot"" title=""Register at Dynadot.com"">Dynadot.com</a></li><li><a href=""/goto/43/eecp19/2/"" target=""_blank"" class=""favicons favnamecheap"" title=""Register at Namecheap.com"">Namecheap.com</a></li><li class=""seperator"">&nbsp;</li><li><a href=""/domain/advocaciamdc.com"" class=""favicons favhomepage"" target=""_blank"" title=""Domain Details on ExpiredDomains.net"">Domain Details</a></li><li><a href=""/goto/116/ebesj8/2/"" target=""_blank"" class=""favicons favgodaddy"" title=""GoDaddy.com Appraisal"">GoDaddy Appraisal</a></li><li><a href=""/goto/25/eep3go/2/"" target=""_blank"" class=""favicons favsemrush"" title=""Check Rankings on SEMRush.com"">SEMRush</a></li><li><a href=""/goto/93/eb1rfr/2/"" target=""_blank"" class=""favicons favtrademarkia"" title=""Check Domain Name on Trademarkia"">Trademarkia</a></li><li><a href=""/goto/7/ec5uh7/2/"" target=""_blank"" class=""favicons favgoogle"" title=""Google the Domain Name"">Google Name</a></li><li><a href=""/goto/11/eekeoy/2/"" target=""_blank"" class=""favicons favgoogle"" title=""Google info:domain.tld"">Google Info</a></li><li><a href=""/goto/15/ef6qyy/2/"" target=""_blank"" class=""favicons favgoogle"" title=""Google site:domain.tld"">Google Site</a></li><li><a href=""/goto/6/eddzzf/2/"" target=""_blank"" class=""favicons favarchiveorg"" title=""Check Website in Wayback Machine"">Wayback Machine</a></li><li><a href=""/goto/9/ebbfv1/2/"" target=""_blank"" class=""favicons favhomepage"" title=""Visit the Website"">Visit Domain</a></li><li><a href=""/goto/8/edemrz/2/"" target=""_blank"" class=""favicons favwhois"" title=""Whois Domain"">Whois Domain</a></li><li><a href=""/goto/21/ecqo3m/2/"" target=""_blank"" class=""favicons favdomaintools"" title=""Check Domainhistory on Domaintools.com"">Domaintools.com</a></li></ul></td> </tr>"; 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