3v4l.org

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<?php $string = "resource_id_heeelp_lala_klopsiki"; preg_match_all('/(_[\w]{1})/', $string, $matches); if(!empty($matches[0])){ foreach($matches[0] as $key){ $result = substr($key, 1, 1); //result is c print $key.' '.ucfirst($result).'<br />'; //$result1=str_replace($result,'',$key);//now your result1 is apitalize //$result2=ucfirst($result1); //now result2 is Apitalize //$finalresult=$result.$result2; ///now your finalresult is cApitalize preg_replace("/$key/", ucfirst($result), $string); } } print $string;
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
_i I<br />_h H<br />_l L<br />_k K<br />resource_id_heeelp_lala_klopsiki

preferences:
299.59 ms | 405 KiB | 460 Q