3v4l.org

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<?php $allowedKeys = array("a","b","c"); $test = array("a" => "asdf", "c" => "asdf", "d" => "asdf"); $notAllowedKeys = array_diff(array_keys($test), $allowedKeys); if($notAllowedKeys) { print "One or more keys are not allowed"; print_r($notAllowedKeys); }

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