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<?php $d = array ( array ( 'a1' => true, 'b1' => 'abc' , 'c1' => 'def' ), array ( 'a2' => true, 'b2' => 'fgh', 'c2' => 'ijk' , 'd2' => 'lmn' , 'e2' => 'opq' )); function flatten(array $array) { $result = array(); if (is_array($array)) { foreach ($array as $k => $v) { if (is_array($v)) { $result = array_merge($result, flatten($v)); } else { $result[$k] = $v; } } } return $result; } $dd = flatten($d); echo "<pre>"; print_r($dd); echo "</pre>"; ?>
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.27, 8.0.0 - 8.0.15, 8.1.0 - 8.1.2
<pre>Array ( [a1] => 1 [b1] => abc [c1] => def [a2] => 1 [b2] => fgh [c2] => ijk [d2] => lmn [e2] => opq ) </pre>

preferences:
28.17 ms | 460 KiB | 5 Q