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<?php $show = array( 'mon' => false, 'tue' => false, 'wed' => false, 'thu' => false, 'fri' => false, 'sat' => false, 'sun' => false ); $keys = array_keys($show); foreach (range(0,6) as $index) { $key = $keys[$index]; $show[$key] |= true; // in your case |= isset($post[$key]); } var_dump($show);
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, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 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 - 8.3.6
array(7) { ["mon"]=> int(1) ["tue"]=> int(1) ["wed"]=> int(1) ["thu"]=> int(1) ["fri"]=> int(1) ["sat"]=> int(1) ["sun"]=> int(1) }

preferences:
218.51 ms | 406 KiB | 327 Q