$my_array = ['foo' => 1, 'hello' => 'world'];
$allowed = ['foo', 'bar'];
$filtered = array_filter(
$my_array,
function ($key) use ($allowed) {
return in_array($key, $allowed);
},
ARRAY_FILTER_USE_KEY
);
<?php
$arr = ['a' => 1, 'b' => 2, 'c' => 3, 'd' => 4];
var_dump(array_filter($arr, function($k) {
return $k == 'b';
}, ARRAY_FILTER_USE_KEY));
var_dump(array_filter($arr, function($v, $k) {
return $k == 'b' || $v == 4;
}, ARRAY_FILTER_USE_BOTH));
?>
$array = [1, 2, 3, 4, 5];
$filtered = array_filter($array, function($item) {
return $item != 4; // Return (include) current item if expression is truthy
});
// $filtered = [1, 2, 3, 5]