php filter array by keys code example
Example 1: php array filter
<?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));
?>
Example 2: filter value in array php return single value
?php
$data= [
0 => [1, 'test1'],
1 => [2, 'test2'],
2 => [3, 'test3'],
];
$ids = array_map(function($item) {
return $item[0];
}, $data);
var_dump($ids);