PHP add values of array

Question

I have an array that looks like this, this array represents number of products in a shopping cart

Array
(
    [0] => Array
        (
            [id] => 1
            [icon] => bus.png
            [name] => Web Development
            [cost] => 500
        )

    [1] => Array
        (
            [id] => 4
            [icon] => icon.png
            [name] => Icon design
            [cost] => 300
        )

    [2] => Array
        (
            [id] => 5
            [icon] => icon.png
            [name] => footer design
            [cost] => 300
        )

)

and i am trying to add the [cost] of each together, since it is a shopping cart I need to display the total. some people might buy single product or 2 or 3 so how do i display the total by adding the cost together I have tried using array_sum($products['cost']) and array_sum($products[0]['cost']) but that does not work

For PHP >= 5.5, `$total = array_sum(array_column($myArray, 'cost'));` — Mark Baker, Jan 19 '15 at 10:57
For earlier versions of PHP: `$total = array_sum(array_map(function($value) { return $value['cost']; }, $myArray));` — Mark Baker, Jan 19 '15 at 10:58
thanks @MarkBaker i will go with a solution on second commend, please add this as an answer so i can accept it — Shairyar, Jan 19 '15 at 11:09

score 1 · Answer 1 · answered Jan 19 '15 at 11:02

1

If you don't want to use any built-in function than you can simply use old technique :)

$sum=0;
foreach ($old as $new) $sum+=$new['cost'];

answered Jan 19 '15 at 11:02

Muhammad Bilal

2,106
1
15
24

http://stackoverflow.com/questions/359732/why-is-it-considered-a-bad-practice-to-omit-curly-braces?lq=1 – Barmar Jan 19 '15 at 11:05

score 1 · Answer 2 · answered Jan 19 '15 at 11:12

Simple use foreach and sum it;

$sum=0;
foreach($product as $key => $value){
    $sum += $value['cost'];
}

Then if you want to sum only the selected products

$sum=0;
foreach($product as $key => $value){
    if(in_array($value['id'], $array_of_selected_product_ids))
        $sum += $value['cost'];
}

score 0 · Accepted Answer · answered Jan 19 '15 at 11:12

For PHP >= 5.5, you can take advantage of PHP's array_column() function

$total = array_sum(
    array_column(
        $myArray, 
        'cost'
    )
);

For earlier versions of PHP, you can emulate this using array_map():

$total = array_sum(
    array_map(
        function($value) { 
            return $value['cost']; 
        }, 
        $myArray
    )
);

PHP add values of array

3 Answers3