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<?php $body = <<<HTML <body class="old_attr"> <div>(content)</div> </body> HTML; $new_class = "new_class_attr"; $body = preg_replace('~<body[^>]*class *= *["\']\K~', "$new_class ", $body, 1, $count); if (!$count) { $body = preg_replace('~<body\K~', " class=\"$new_class\"", $body, 1); } echo $body;
Output for 5.6.38, 7.1.0 - 7.1.25, 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 - 8.3.4, 8.3.6 - 8.3.7
<body class="new_class_attr old_attr"> <div>(content)</div> </body>
Output for 8.3.5
Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 <body class="new_class_attr old_attr"> <div>(content)</div> </body>
preferences:
185.86 ms | 402 KiB | 180 Q