从数组中获取空值


Getting empty value from array

我有以下代码,$totalDonations应该输出1500。

<?php
    $donations = $wpdb->get_results("
      SELECT amount
      FROM wp_fullstripe_payments
    ");
?>
<?php $totalDonations = array_sum($donations); ?>
<?php echo $totalDonations; ?>

我从$totalDonations中得到0。

下面是$捐款的var_dump:

array(2) { [0]=> object(stdClass)#2108 (1) { ["amount"]=> string(3) "500" } [1]=> object(stdClass)#2107 (1) { ["amount"]=> string(4) "1000" } }

这个也不行:

<?php echo $donations[0]; ?>

您将获得作为stdClass的结果

<?php 
     $totalDonations;
     foreach ($donation as $donations){
       totalDonations += $donation->amount;
     } 
?>

查看此链接:http://www.webmaster-source.com/2009/08/20/php-stdclass-storing-data-object-instead-array/