获取具有 stdClass 对象列的行并求和具有相同 id 的元素

Posted 2023-02-24

【中文标题】获取具有 stdClass 对象列的行并求和具有相同 id 的元素

【英文标题】：Get rows with stdClass objects column and sum elements with same id

【发布时间】：2017-09-17 12:58:53

【问题描述】：

我有一个订单表，其中一列名为“ordered_goods”如下所示：

"["product_id":"3","qua":"3","we":"1350","product_id":"4","qua":"3","we":"1215","product_id":"5","qua":"5","we":"810"]"

当我收到所有“status = 0”的订单时，它看起来像这样：

$orders_status_zero   =   $this->db->get_where('orders', array('status' => '0'))->result_array();
foreach ($orders_status_zero as $row):
print_r($row['ordered_goods']); // RESULT:

["product_id":"3","qua":"3","we":"1350","product_id":"4","qua":"3","we":"1215","product_id":"5","qua":"5","we":"810"]
["product_id":"3","qua":"4","we":"1350","product_id":"4","qua":"4","we":"1620","product_id":"5","qua":"4","we":"648","product_id":"6","qua":"5","we":"864","product_id":"8","qua":"4","we":"864"]
["product_id":"3","qua":"4","we":"1800","product_id":"4","qua":"3","we":"1215","product_id":"6","qua":"4","we":"864"]

我正在尝试对所有“qua”求和，其中“product_id”= 3。

我尝试了很多方法，但都没有成功。显然我不知道该怎么做。

提前感谢您的帮助。

【参考方案1】：

如果您的列 ordered_goods 存储的是 json，您可以这样做

$amount = 0;
foreach ($orders_status_zero as $row)
    $array = (array)json_decode($row['ordered_goods']);
    $amount +=  array_sum(array_map(function($element) 
        if($element->product_id == 3) 
            return $element->qua; 
    , $array));

Array map 将数组作为第二个参数（在本例中为每一行的ordered_goods），第一个参数是一个匿名函数，它将数组的每个元素作为参数。当找到 id = 3 的产品时，返回 qua 属性并将其与 array_sum 相加为 $amount

【讨论】：

感谢您的回复和解释。这两天我一直在苦苦挣扎。非常感谢！