通过PHP中对象值的总和对多维数组进行排序

Question

I have the below multi dimensional array of products. Each array is a pair of products that make a product set, I need to order the multi dimensional array by the total price of each product set.

array(4) {
  [0]=>
  array(2) {
    ["product1"]=>
    object(stdClass)#5075 (2) {
      ["product_id"]=>
      string(4) "9416"
      ["price"]=>
      string(6) "110.00"
    }
    ["product2"]=>
    object(stdClass)#5077 (2) {
      ["product_id"]=>
      string(4) "9431"
      ["price"]=>
      string(6) "100.00"
    }
  }
  [1]=>
  array(2) {
    ["product1"]=>
    object(stdClass)#5065 (2) {
      ["product_id"]=>
      string(4) "1254"
      ["price"]=>
      string(6) "75.00"
    }
    ["product2"]=>
    object(stdClass)#5067 (2) {
      ["product_id"]=>
      string(4) "9431"
      ["price"]=>
      string(6) "62.00"
    }
  }
  [2]=>
  array(2) {
    ["product1"]=>
    object(stdClass)#5055 (2) {
      ["product_id"]=>
      string(4) "9416"
      ["price"]=>
      string(6) "45.00"
    }
    ["product2"]=>
    object(stdClass)#5057 (2) {
      ["product_id"]=>
      string(4) "9431"
      ["price"]=>
      string(6) "50.00"
    }
  }
  [3]=>
  array(2) {
    ["product1"]=>
    object(stdClass)#5045 (2) {
      ["product_id"]=>
      string(4) "9416"
      ["price"]=>
      string(6) "60.00"
    }
    ["product2"]=>
    object(stdClass)#5047 (2) {
      ["product_id"]=>
      string(4) "9431"
      ["price"]=>
      string(6) "25.00"
    }
  }
}

I need to sort the multi-dimensional array by the total sum of product1 + product2 in each array in ascending order. For example [1] should be above [0] as 75+62 is less than 110 +100.

If anyone can help me with this it would be greatly appreciated.

Answer 1

You can use usort() for this purpose:-

function comparePrice($a,$b)
{
  $a_price = $a['product1']->price + $a['product2']->price;
  $b_price = $b['product1']->price + $b['product2']->price;
  if ($a_price ==$b_price) return 0;
  return ($a_price<$b_price)? -1:1;
}
usort($array,'comparePrice');

A hardcoded working example:- https://3v4l.org/mTfu6

Answer 2

You need to use user-defined sorting

http://php.net/manual/en/function.usort.php

usort($products, function($a, $b) {
    $prodA = $a['product1']['price'] + $a['product2']['price'];
    $prodB = $b['product1']['price'] + $b['product2']['price'];

    if($prodA == $prodB) return 0;
    return ($prodA < $prodB) ? -1 : 1;
});

Answer 3

The php7+ "spaceship operator" (aka three-way-comparison operator) makes the syntax with usort() as clean and brief as possible.

Code: ( Demo )

$array = [
    [
        "product1" => (object) ["product_id" => "9416", "price"=>"110.00"],
        "product2" => (object) ["product_id"=>"9431", "price"=>"100.00"]
    ],
    [
        "product1" => (object) ["product_id" => "1254", "price"=>"75.00"],
        "product2" => (object) ["product_id"=>"9431", "price"=>"62.00"]
    ],
    [
        "product1" => (object) ["product_id" => "9416", "price"=>"45.00"],
        "product2" => (object) ["product_id"=>"9431", "price"=>"50.00"]
    ],
    [
        "product1" => (object) ["product_id" => "9416", "price"=>"60.00"],
        "product2" => (object) ["product_id"=>"9431", "price"=>"25.00"]
    ]
];

usort($array, function($a, $b) {
    return $a['product1']->price + $a['product2']->price <=> $b['product1']->price + $b['product2']->price;
});

var_export($array);

Output:

array (
  0 =>                                // sum = 85.00
  array (
    'product1' => 
    (object) array(
       'product_id' => '9416',
       'price' => '60.00',
    ),
    'product2' => 
    (object) array(
       'product_id' => '9431',
       'price' => '25.00',
    ),
  ),
  1 =>                                // sum = 95.00 
  array (
    'product1' => 
    (object) array(
       'product_id' => '9416',
       'price' => '45.00',
    ),
    'product2' => 
    (object) array(
       'product_id' => '9431',
       'price' => '50.00',
    ),
  ),
  2 =>                                // sum = 137.00 
  array (
    'product1' => 
    (object) array(
       'product_id' => '1254',
       'price' => '75.00',
    ),
    'product2' => 
    (object) array(
       'product_id' => '9431',
       'price' => '62.00',
    ),
  ),
  3 =>                                // sum = 210.00 
  array (
    'product1' => 
    (object) array(
       'product_id' => '9416',
       'price' => '110.00',
    ),
    'product2' => 
    (object) array(
       'product_id' => '9431',
       'price' => '100.00',
    ),
  ),
)