CODEWITHSUNDEEP
phparraysmultidimensional-arraycount
John
John

Reputation: 387

Weird values when calculating number of items in a multidimensional array

I'm having problems return a correct number of items in a multidimensional array and i have no idea what I'm doing wrong so I'm kinda confused.

// Build test array

$marks = Array();

$marks[] = array("id" => 1, "parent_id" => "0", "title" => "Games");
$marks[] = array("id" => 2, "parent_id" => "0", "title" => "Food");
$marks[] = array("id" => 3, "parent_id" => "0", "title" => "Houses");
$marks[] = array("id" => 4, "parent_id" => "0", "title" => "Cities");

$marks[2]['child'][] = array("id" => 4, "parent_id" => "0", "title" => "Big House");
$marks[2]['child'][] = array("id" => 4, "parent_id" => "0", "title" => "Small House");
$marks[2]['child'][] = array("id" => 4, "parent_id" => "0", "title" => "Castle");

$marks[2]['child'][1]['child'][] = array("id" => 4, "parent_id" => "0", "title" => "Living Room");
$marks[2]['child'][1]['child'][] = array("id" => 4, "parent_id" => "0", "title" => "Kitchen");

    function count_recursive ($array, $limit) { 
        $count = 0; 
        foreach ($array as $id => $_array) { 
            if (is_array ($_array) && $limit > 0) { 
                $count += count_recursive ($_array, $limit - 1); 
            } else { 
                $count += 1; 
            } 
        } 
        return $count; 
    } 

echo '###' . count_recursive($marks, 5);

echo '<pre>' . print_r($marks, 1) . '</pre>';

The odd thing is that it's returning 27?? I don't understand where it gets that value when it's supposed to be 9.

I also tested

echo count($marks, COUNT_RECURSIVE);

But it returns 38 so I'm really confused!

Help would be much appreciated.

Upvotes: 0

Views: 37

Answers (1)

Paul Kienitz
Paul Kienitz

Reputation: 878

You're counting the fields in the arrays. You seem to be asking how to count whole arrays that each have an id and so on -- that's what would yield 9. To do that, instead on incrementing the count when is_array is false, increment when it's true. Instead of passing that element back in recursively, see if it has a ['child'] and pass that recursively. Otherwise the 'child' collection itself gets counted and you get 11. Or, you could increment the counter only if 'id' is set.

Here's how COUNT_RECURSIVE gets 38:

$marks has four values, indexed as 0, 1, 2, and 3. That makes a count of 4.

$marks[0] through $marks[3] each have three named elements: 'id', 'parent_id', and 'title', together making 12. The count is now 16.

$marks[2] has a 'child' also. That makes 17.

$marks[2]['child'] has three elements indexed as 0, 1, and 2. That makes 20.

Each of those has three named elements, making 29.

$marks[2]['child'][1] has a 'child', making 30.

That has elements 0 and 1, making 32.

Each of those two has three named elements. 38.

Upvotes: 1

Related Questions