Question

假设我在PHP中有此数组：

Array
(
    [0] => Array
        (
            [name] => Banana
            [quantity] => 124
        )
    [1] => Array
        (
            [name] => Cherry
            [quantity] => 24
        )
    [2] => Array
        (
            [name] => Apple
            [quantity] => 224
        )

)

如何用键quantity将数字相加？

谢谢。

Answer 1

请随时与我们分享您的尝试。

它对我们有很大帮助。

您可以使用：

$arr = [['name' => "Banana", 'quantity' => 124], ['name' => "Cherry", 'quantity' => 24], ['name' => "Apple", 'quantity' => 224]];

$sum = 0;
foreach ($arr as $item) {
    $sum += $item['quantity'];
}

或者（PHP 5.5 +）：

$sum = array_sum(array_column($arr, 'quantity'));

Answer 2

/*
    Receives a Multidemensional Array (Matrix) and returns the sum of quantity.
    Returns -1 on fail.
*/
function SumKeyOfArray($Matrix)
{
    if(!empty($Matrix))
    {
        $sum = 0;       
        foreach($Matrix as $array)
        {
            if(isset($array['quantity']))
                $sum = $sum + $array['quantity'];
        }
        return $sum;
    }
    return -1;
}

Answer 3

另一种选择是使用reduce函数：

$arr= [['name' => "Banana", 'quantity' => 124], ['name' => "Cherry", 'quantity' => 24], ['name' => "Apple", 'quantity' => 224]];

echo array_reduce($arr, function($sum, $elem) {
    return $sum += $elem["quantity"];
});

来自PHP多维数组的值求和

3 个答案: