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  1. <?php
  2.  
  3. $output = '[vc_tab [vc_tab [vc_tab [vc_tab [vc_tab';
  4.  
  5. $active = 3;     // target occurrence
  6. $occurrence = 0; // counter
  7. $output = preg_replace_callback(
  8.     '/\[vc_tab/',
  9.     function ($matches) use(&$occurrence, $active) {
  10.         return ++$occurrence != $active
  11.             ? $matches[0]
  12.             : '[vc_tab active="true"';
  13.     },
  14.     $output
  15. );
  16.  
  17. echo $output;
Success #stdin #stdout 0.01s 20520KB
comments (?)
stdin 
Standard input is empty
stdout 
[vc_tab [vc_tab [vc_tab active="true" [vc_tab [vc_tab
https://ideone.com/K6YJql
language:
PHP (php 7.3.5)
created:
11 years ago
visibility:
public

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