Question

我有$test数组

        Array
(
    [0] => Array
        (
            [quantity] => 3
            [stock_id] => _PHONE
        )

    [1] => Array
        (
            [quantity] => 3
            [stock_id] => 102
        )

    [2] => Array
        (
            [quantity] => 4
            [stock_id] => _PHONE
        )

    [3] => Array
        (
            [quantity] => 3
            [stock_id] => 102
        )

    [4] => Array
        (
            [quantity] => 4
            [stock_id] => _PHONE
        )

    [5] => Array
        (
            [quantity] => 6
            [stock_id] => _PHONE
        )

    [6] => Array
        (
            [quantity] => 2
            [stock_id] => 102
        )

)

并将相同的stock_id键加到一个，我使用以下函数：

function sum($array, $key){
    isset($array[$key['stock_id']]) ? $array[$key['stock_id']]['quantity'] += $key['quantity'] : $array[$key['stock_id']] = $key;  
    return $array;
};

//merge same stock_id and sum the quantity same stock id
$sum_same_stock_id = array_reduce($test, "sum");

结果如下：

$ sum_same_stock_id：

Array
(
    [_PHONE] => Array
        (
            [quantity] => 17
            [stock_id] => _PHONE
        )

    [102] => Array
        (
            [quantity] => 8
            [stock_id] => 102
        )

)

所以这里的问题是，我想传递一个动态键值而不仅仅是固定值stock_id＆amp;上面quantity函数中的sum。尝试了多种方式，但仍然无法找到方法。我们也可以把这些功能放到课堂上吗？

任何建议表示赞赏！

Answer 1

首先想到的是在数组中再创建两个键，用于存储所需的值。第三个参数包含初始值。像这样：

let!

array_reduce使用动态变量传递第二个函数

1 个答案: