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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/

Test String

Code Generator

Generated Code

import Foundation let pattern = #"<div class="instant_search_title fsl fwb fcb"><a href=".+?">(.*?)<"# let regex = try! NSRegularExpression(pattern: pattern) let testString = ##""" <i class="mrs friendsIcon customimg img sp_b6fmvb sx_5e511f"><u>Friend</u></i><span class="uiButtonText">Friends</span></a></div></div><div class="pls"><div class="instant_search_title fsl fwb fcb"><a href="https://www.facebook.com/adrianasdzxc" onclick="if (event.button == 0) &#123; search_logged_ajax(&#123;&quot;ab&quot;:&quot;T_GS_BACKEND_ENTITY_LIMITATION&quot;,&quot;cururl&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;fc&quot;:1,&quot;gc&quot;:0,&quot;id&quot;:616226XXX,&quot;init&quot;:&quot;s:unknown&quot;,&quot;is_friend&quot;:true,&quot;is_new_user&quot;:0,&quot;locale&quot;:&quot;en_US&quot;,&quot;o_type&quot;:1,&quot;original_q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;rank&quot;:0,&quot;rc&quot;:0,&quot;sid&quot;:&quot;10000108681XXXX.3365508868..1&quot;,&quot;start&quot;:0,&quot;typeahead_sid&quot;:null,&quot;u&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;t&quot;:&quot;c:name&quot;&#125;); &#125;" onmouseup="if (event.button != 0) &#123; search_logged_ajax(&#123;&quot;ab&quot;:&quot;T_GS_BACKEND_ENTITY_LIMITATION&quot;,&quot;cururl&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;fc&quot;:1,&quot;gc&quot;:0,&quot;id&quot;:616226XXX,&quot;init&quot;:&quot;s:unknown&quot;,&quot;is_friend&quot;:true,&quot;is_new_user&quot;:0,&quot;locale&quot;:&quot;en_US&quot;,&quot;o_type&quot;:1,&quot;original_q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;rank&quot;:0,&quot;rc&quot;:0,&quot;sid&quot;:&quot;10000108681XXXX.3365508868..1&quot;,&quot;start&quot;:0,&quot;typeahead_sid&quot;:null,&quot;u&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;t&quot;:&quot;c:name&quot;&#125;); &#125;" data-hovercard="/ajax/hovercard/user.php?id=616226XXX">Adrian asdzxc</a></div><div class="fsm fwn fcg"><div class="fbProfileByline searchResultPersonByline"><span class="fbProfileBylineFragment"><span class="fbProfileBylineIconContainer"><i class="mrs fbProfileBylineIcon img sp_9pvis2 sx_897cc1"></i></span><span class="fbProfileBylineLabel">Webmaster at <a href="true"><a href="https://www.facebook.com/pages/Freelancer/640564905962853" data-hovercard="/ajax/hovercard/page.php?id=640564905962853">Freelancer</a></a></span></span><span class="fbProfileBylineFragment"><span class="fbProfileBylineIconContainer"><i class="mrs fbProfileBylineIcon img sp_9pvis2 sx_ed189a"></i></span><span class="fbProfileBylineLabel">Studied Web Design at <a href="true"><a href="https://www.facebook.com/pages/Universitatea-Tibiscus/242668875759811" data-hovercard="/ajax/hovercard/page.php?id=242668875759811">Universitatea Tibiscus</a></a></span></span><span class="fbProfileBylineFragment"><span class="fbProfileBylineIconContainer"><i class="mrs fbProfileBylineIcon img sp_9pvis2 sx_c1d4c8"></i></span><span class="fbProfileBylineLabel">Lives in <a href="true"><a href="https://www.facebook.com/pages/Timi%C8%99oara-poland/107982459236366" data-hovercard="/ajax/hovercard/page.php?id=107982459236366">Timișoara, poland</a></a></span></span></div></div><div><div class="mts detailedsearch_actions"><a href="/browse/mutual_friends/?uid=616226XXX" rel="dialog" ajaxify="/ajax/browser/dialog/mutual_friends/?uid=616226XXX" onclick="if (event.button == 0) &#123; search_logged_ajax(&#123;&quot;ab&quot;:&quot;T_GS_BACKEND_ENTITY_LIMITATION&quot;,&quot;cururl&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;fc&quot;:1,&quot;gc&quot;:0,&quot;id&quot;:616226XXX,&quot;init&quot;:&quot;s:unknown&quot;,&quot;is_friend&quot;:true,&quot;is_new_user&quot;:0,&quot;locale&quot;:&quot;en_US&quot;,&quot;o_type&quot;:1,&quot;original_q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;rank&quot;:0,&quot;rc&quot;:0,&quot;sid&quot;:&quot;10000108681XXXX.3365508868..1&quot;,&quot;start&quot;:0,&quot;typeahead_sid&quot;:null,&quot;u&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;t&quot;:&quot;c:mutual_friend&quot;&#125;); &#125;" onmouseup="if (event.button != 0) &#123; search_logged_ajax(&#123;&quot;ab&quot;:&quot;T_GS_BACKEND_ENTITY_LIMITATION&quot;,&quot;cururl&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;fc&quot;:1,&quot;gc&quot;:0,&quot;id&quot;:616226XXX,&quot;init&quot;:&quot;s:unknown&quot;,&quot;is_friend&quot;:true,&quot;is_new_user&quot;:0,&quot;locale&quot;:&quot;en_US&quot;,&quot;o_type&quot;:1,&quot;original_q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;rank&quot;:0,&quot;rc&quot;:0,&quot;sid&quot;:&quot;10000108681XXXX.3365508868..1&quot;,&quot;start&quot;:0,&quot;typeahead_sid&quot;:null,&quot;u&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;t&quot;:&quot;c:mutual_friend&quot;&#125;); &#125;" role="button">2 mutual friends</a> · <a href="/messages/adrianasdzxc" ajaxify="/ajax/messaging/composer.php?ids%5B0%5D=616226XXX&amp;ref=search" rel="dialog" onclick="if (event.button == 0) &#123; search_logged_ajax(&#123;&quot;ab&quot;:&quot;T_GS_BACKEND_ENTITY_LIMITATION&quot;,&quot;cururl&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;fc&quot;:1,&quot;gc&quot;:0,&quot;id&quot;:616226XXX,&quot;init&quot;:&quot;s:unknown&quot;,&quot;is_friend&quot;:true,&quot;is_new_user&quot;:0,&quot;locale&quot;:&quot;en_US&quot;,&quot;o_type&quot;:1,&quot;original_q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;rank&quot;:0,&quot;rc&quot;:0,&quot;sid&quot;:&quot;10000108681XXXX.3365508868..1&quot;,&quot;start&quot;:0,&quot;typeahead_sid&quot;:null,&quot;u&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;t&quot;:&quot;c:action&quot;&#125;); &#125;" onmouseup="if (event.button != 0) &#123; search_logged_ajax(&#123;&quot;ab&quot;:&quot;T_GS_BACKEND_ENTITY_LIMITATION&quot;,&quot;cururl&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;fc&quot;:1,&quot;gc&quot;:0,&quot;id&quot;:616226XXX,&quot;init&quot;:&quot;s:unknown&quot;,&quot;is_friend&quot;:true,&quot;is_new_user&quot;:0,&quot;locale&quot;:&quot;en_US&quot;,&quot;o_type&quot;:1,&quot;original_q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;q&quot;:&quot;adriantnt\\u0040yahoo.com&quot;,&quot;rank&quot;:0,&quot;rc&quot;:0,&quot;sid&quot;:&quot;10000108681XXXX.3365508868..1&quot;,&quot;start&quot;:0,&quot;typeahead_sid&quot;:null,&quot;u&quot;:&quot;https:\\/\\/www.facebook.com\\/adrianasdzxc&quot;,&quot;t&quot;:&quot;c:action&quot;&#125;); &#125;" role="button">Send message</a></div></div></div></div></div></div></div> --></code> """## let stringRange = NSRange(location: 0, length: testString.utf16.count) if let firstMatch = regex.firstMatch(in: testString, range: stringRange) { let result: [String] = (1 ..< firstMatch.numberOfRanges).map { (testString as NSString).substring(with: firstMatch.range(at: $0)) } print(result) } else { print("No matches were found.") }

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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression