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

/
/

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

using System; using System.Text.RegularExpressions; public class Example { public static void Main() { string pattern = @"\h*<xen:if is=""{\$debugMode}""> \h*<xen:if hascontent=""true""> \h*<dl class=""pairsInline debugInfo"".*?> (\h*)<xen:contentcheck>"; string substitution = @"$0\n$1 <!-- Adding XenForo version strings -->\n$1 <dt>XenForo Version:<dt> <dd>{$xenOptions.currentVersion} ({$xenOptions.currentVersionId})</dd>\n\n"; string input = @"<xen:edithint template=""footer.css"" /> <xen:hook name=""footer""> <div class=""footer""> <div class=""pageWidth""> <div class=""pageContent""> <xen:if is=""{$canChangeStyle} OR {$canChangeLanguage}""> <dl class=""choosers""> <xen:if is=""{$canChangeStyle}""> <dt>{xen:phrase style}</dt> <dd><a href=""{xen:link 'misc/style', '', 'redirect={$requestPaths.requestUri}'}"" class=""OverlayTrigger Tooltip"" title=""{xen:phrase style_chooser}"" rel=""nofollow"">{$visitorStyle.title}</a></dd> </xen:if> <xen:if is=""{$canChangeLanguage}""> <dt>{xen:phrase language}</dt> <dd><a href=""{xen:link 'misc/language', '', 'redirect={$requestPaths.requestUri}'}"" class=""OverlayTrigger Tooltip"" title=""{xen:phrase language_chooser}"" rel=""nofollow"">{$visitorLanguage.title}</a></dd> </xen:if> </dl> </xen:if> <ul class=""footerLinks""> <xen:hook name=""footer_links""> <xen:if is=""{$xenOptions.contactUrl.type} === 'default'""> <li><a href=""{xen:link 'misc/contact'}"" class=""OverlayTrigger"" data-overlayOptions=""{&quot;fixed&quot;:false}"">{xen:phrase contact_us}</a></li> <xen:elseif is=""{$xenOptions.contactUrl.type} === 'custom'"" /> <li><a href=""{$xenOptions.contactUrl.custom}"" {xen:if {$xenOptions.contactUrl.overlay}, 'class=""OverlayTrigger"" data-overlayOptions=""{&quot;fixed&quot;:false}""'}>{xen:phrase contact_us}</a></li> </xen:if> <li><a href=""{xen:link help}"">{xen:phrase help}</a></li> <xen:if is=""{$homeLink}""><li><a href=""{$homeLink}"" class=""homeLink"">{xen:phrase home}</a></li></xen:if> <li><a href=""{$requestPaths.requestUri}#navigation"" class=""topLink"">{xen:phrase go_to_top}</a></li> <li><a href=""{xen:link forums/-/index.rss}"" rel=""alternate"" class=""globalFeed"" target=""_blank"" title=""{xen:phrase rss_feed_for_x, 'title={$xenOptions.boardTitle}'}"">{xen:phrase rss}</a></li> </xen:hook> </ul> <span class=""helper""></span> </div> </div> </div> <div class=""footerLegal""> <div class=""pageWidth""> <div class=""pageContent""> <ul id=""legal""> <xen:hook name=""footer_links_legal""> <xen:if is=""{$tosUrl}""><li><a href=""{$tosUrl}"">{xen:phrase terms_and_rules}</a></li></xen:if> <xen:if is=""{$xenOptions.privacyPolicyUrl}""><li><a href=""{$xenOptions.privacyPolicyUrl}"">{xen:phrase privacy_policy}</a></li></xen:if> </xen:hook> </ul> <div id=""copyright"">{xen:helper copyright} {xen:phrase extra_copyright}</div> <xen:hook name=""footer_after_copyright"" /> <xen:if is=""{$debugMode}""> <xen:if hascontent=""true""> <dl class=""pairsInline debugInfo"" title=""{$controllerName}-&gt;{$controllerAction}{xen:if $viewName, ' ({$viewName})'}""> <xen:contentcheck> <xen:if is=""{$page_time}""><dt>{xen:phrase timing}:</dt> <dd><a href=""{$debug_url}"" rel=""nofollow"">{xen:phrase x_seconds, 'time={xen:number $page_time, 4}'}</a></dd></xen:if> <xen:if is=""{$memory_usage}""><dt>{xen:phrase memory}:</dt> <dd>{xen:phrase x_mb, 'size={xen:number {xen:calc ""{$memory_usage} / 1024 / 1024""}, 3}'}</dd></xen:if> <xen:if is=""{$db_queries}""><dt>{xen:phrase db_queries}:</dt> <dd>{xen:number {$db_queries}}</dd></xen:if> </xen:contentcheck> </dl> </xen:if> </xen:if> <span class=""helper""></span> </div> </div> </div> </xen:hook>"; Regex regex = new Regex(pattern); string result = regex.Replace(input, substitution, 1); } }

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