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<?php $a = array("test"=>"1", "test2"=>2, "test3"=>3); $needed = array("test", "test2"); foreach($a as $i => $v) { if(!in_array($i, $needed)) { unset($a[$i]); } } print_r($a);
based on ru9Zv
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, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.6 - 7.2.33, 7.3.0 - 7.3.27, 7.4.0 - 7.4.15, 8.0.0 - 8.0.2
Array ( [test] => 1 [test2] => 2 )