I cant get my head around how to do this.
Consider I have the following php array
Array
(
[0] => Array
(
[cat_id] => 2
[parent_id] => 1
[Title] => Default Category
[Product Count] => 0
[children] => Array
(
[0] => Array
(
[cat_id] => 4
[parent_id] => 2
[Title] => computers & electronics
[Product Count] => 5
[children] => Array
(
[0] => Array
(
[cat_id] => 5
[parent_id] => 4
[Title] => projectors
[Product Count] => 2
[children] => Array
(
[0] => Array
(
[cat_id] => 6
[parent_id] => 5
[Title] => film projectors
[Product Count] => 1
)
[1] => Array
(
[cat_id] => 7
[parent_id] => 4
[Title] => projector cases
[Product Count] => 0
children] => Array
(
[0] => Array
(
[cat_id] => 8
[parent_id] => 7
[Title] => leather cases
[Product Count] => 10
I want to somehow iterate over each array element and total up the Product Count element based on its on value and all child values (which could be n levels deep)
The end result I am looking for is
Array
(
[0] => Array
(
[cat_id] => 2
[parent_id] => 1
[Title] => Default Category
[Product Count] => 18
[children] => Array
(
[0] => Array
(
[cat_id] => 4
[parent_id] => 2
[Title] => computers & electronics
[Product Count] => 18
[children] => Array
(
[0] => Array
(
[cat_id] => 5
[parent_id] => 4
[Title] => projectors
[Product Count] => 3
[children] => Array
(
[0] => Array
(
[cat_id] => 6
[parent_id] => 5
[Title] => film projectors
[Product Count] => 1
)
[1] => Array
(
[cat_id] => 7
[parent_id] => 4
[Title] => projector cases
[Product Count] => 10
children] => Array
(
[0] => Array
(
[cat_id] => 8
[parent_id] => 7
[Title] => leather cases
[Product Count] => 10
can anyone help please? Speed or efficiency is not really a major issue as this will be run once a day at 3 in the morning so no-one will be waiting for it to finish its work!!
The only reasonable way to tally up values in an array with unknown depth is by using recursive methods.
function sumItems(&$branch,$sum){
$sum = $branch['Product Count'];
foreach($branch['children'] as &$item){
$sum += sumItems($item,$sum); // Each sub array runs this function
// And adds thier count to the parent branch
}
$branch['Product Count'] = $sum; // Since branch is passed to function as
// Reference, this line overrides the original value
return $sum; // Each recursion of this function returns its own value + the sum of all sub arrays to the parent
}
sum_items($array,0); // Will return the sum of all branches and sub branches