How to resolve the issue of invalid usage of array_inte…

There could be a few possible reasons why the array_intersect() function is not working.

1. perform a mapping operation on each element of an array

$array1 = ['1', '2', '3'];
$array2 = [2, 3, 4];

$array1 = array_map('intval', $array1);

$result = array_intersect($array1, $array2);
print_r($result);

1. The values in an array are objects, but objects are compared by reference rather than by value. If you want to compare the property values of objects, you can achieve this by customizing an anonymous function.

class Item {
    private $id;

    public function __construct($id) {
        $this->id = $id;
    }

    public function getId() {
        return $this->id;
    }
}

$item1 = new Item(1);
$item2 = new Item(2);
$item3 = new Item(3);

$array1 = [$item1, $item2];
$array2 = [$item2, $item3];

$result = array_intersect($array1, $array2);
print_r($result); // []

$result = array_uintersect($array1, $array2, function($a, $b) {
    return $a->getId() <=> $b->getId();
});
print_r($result); // [$item2]

Please make sure the data types being compared are consistent and use the appropriate comparison function according to your needs.