如何根据内部内容获取数组的总值

Question

这是我的数组，

[Computers] => Array
(
   [0] => Array
       (
           [product_id] => 78
           [price] => 999.99
           [quantity] => 2
       )

   [1] => Array
       (
           [product_id] => 70
           [price] => 49.99
           [quantity] => 6
       )

)


[Scanners] => Array
(
   [0] => Array
       (
           [product_id] => 65
           [price] => 99.99
           [quantity] => 7
       )
   [1] => Array
       (
           [product_id] => 70
           [price] => 149.99
           [quantity] => 5
       )
   [2] => Array
       (
           [product_id] => 70
           [price] => 10.99
           [quantity] => 1
       )

)

我正在寻找一种方法根据内部数组来汇总外部数组的值

，例如 Computers 数组有两种产品，我需要根据数量获取总计。例如，计算机数组的 (999.99 *2) + (49.99 * 6) = 2299.92 等等......

Answer 1

这是一个未经测试的解决方案，但我不明白为什么它不起作用

$sum = 0;
foreach($array as $key => $value) {
    $sum += $value['quantity'] * $value['price'];
}

Answer 2

这是一种替代方法，将产品映射到小计，然后对外部数组中每个项目的小计求和。

$totals = array_map(function($group){
    return array_sum(array_map(function($product) {
        return $product['price'] * $product['quantity'];
    }, $group));
}, $array);

var_dump($totals, array_sum($totals));

Answer 3

试试这个代码：

$sum=0;
foreach ($computers as $pc) {
   $sum += ($pc["price"] * $pc["quantity"]);
}

Answer 4

  $total = 0;
  for( $i = 0; $i < count( Computers ); $i++ ){
       $total += ( Computers[$i]['price'] * Computers[$i]['quantity'] );
  }