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

Code Generator

Language

Generated Code

use strict; my $str = '<p><em>ขอขอบคุณข้อมูลจาก <a href="https://www.facebook.com/CrewabsCabincrew/photos/a.163266007065328.35057.162290157162913/981295968595657/?type=3">เฟซบุ๊ก Crewabs Cabincrew</a></em></p> <script type="text/javascript"></script>asdasd asdasdasd asdad <script type="text/javascript">// <![CDATA[ (function(d, s, id) { var js, fjs = d.getElementsByTagName(s)[0]; if (d.getElementById(id)) return; js = d.createElement(s); js.id = id; js.src = "//connect.facebook.net/th_TH/sdk.js#xfbml=1&version=v2.3"; fjs.parentNode.insertBefore(js, fjs);}(document, \'script\', \'facebook-jssdk\')); // ]]></script> <div class="fb-post" data-href="https://www.facebook.com/CrewabsCabincrew/photos/a.163266007065328.35057.162290157162913/981295968595657/?type=3" data-width="500"> <div class="fb-xfbml-parse-ignore"> <blockquote cite="https://www.facebook.com/CrewabsCabincrew/photos/a.163266007065328.35057.162290157162913/981295968595657/?type=3"> <p>จากใจแอร์สาวบนไฟล์ทที่โดนหนุ่มรถไฟจีบด้วยมุก"ระเบิด"กรณีหนุ่มรถไฟ แซวแอร์ไทยไลอ้อน อยากขอพื้นที่ชี้แจงให้ลูกเรือสาวในไ...</p> Posted by <a href="https://www.facebook.com/CrewabsCabincrew/">Crewabs Cabincrew</a> on&nbsp;<a href="https://www.facebook.com/CrewabsCabincrew/photos/a.163266007065328.35057.162290157162913/981295968595657/?type=3">3 พฤศจิกายน 2015</a></blockquote> </div> </div> </div> </div>'; my $regex = qr/<script[^>]+>[\s|\S]*('facebook-jssdk'\)\); \/\/ ]]><\/script>)/p; if ( $str =~ /$regex/ ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html