PHP 数组处理：去除空元素的实用技巧

$array = [1, 2, '', 3, null, 4];

$array = array_filter($array, function($value) {
    return $value !== '' && $value !== null;
});
print_r($array);

$array = [1, 2, '', 3, null, 4];

foreach ($array as $key => $value) {
    if ($value === '' || $value === null) {
        unset($array[$key]);
    }
}
print_r($array);

$array = [[1, 2, '', 3], [null, 4, '', 5]];

$array = array_map(function($sub_array) {
    return array_filter($sub_array, function($value) {
        return $value !== '' && $value !== null;
    });
}, $array);
print_r($array);

Array

(
    [0] => Array
        (
            [0] => 1
            [1] => 2
            [3] => 3
        )

    [1] => Array
        (
            [1] => 4
            [3] => 5
        )

)