hierarchical structure in array, recursion in php

Question

i have hierarchical structure in array like this:

item root 1
- item child 1
-- item child 2
 item root 2
- item child

i want to get:

1. item root 1
 1-1. item child 1
 1-1-1. item child 2
2. item root 2
 2-1. item child

My function to build tree

function printTree($data, $level = 0, $counter = 1) { 

            foreach ($data as $item) {  

                if ($item['parent_id'] == 0) {
                    $addr =  $counter . '. ' . $item['address'];
                    $counter++;
                }

                else if ($item['parent_id'] != 0) {                        

                   $addr = $counter . '-' . $counter . ' ' . $item['address'];                   



                } else {
                     $addr = $item['address'];              
                }

                global $result;

                $result['aaData'][] = Array(
                 $addr,
                 $item['mask'],
                 $item['status'],
                 $item['subnets'],
                 $item['therange'] = $item['start'] . ' - ' . $item['end'],
                 $item['type'],
                 $item['node'],
                 $item['id'],                               
             );   

                if (isset($item['children'])) {                    
                    printTree($item['children'], $level + 1, $counter + 1);
                }


            }

            return $result;        
        }

But my result is incorrect, root's element count normal, but childs wrong, how can i fix this? need help, thanks!

Answer 1

Here is some code, with your specific test case:

EDIT (corrected with $counter, not id)

function makeTree($data, $pre='') {
  $result = array();
  $counter = 1;

  if (is_array($data)) foreach ($data as $item) {
    $result[] = $pre.$counter.' '.$item['address'];
    if (isset($item['children']) && is_array($item['children'])) {
      $result = array_merge($result, makeTree($item['children'], $pre.$counter.'-'));
    }
    $counter++;
  }

  return $result;
}

$data = array(
  array(
    'id' => 1,
    'address' => 'addy 1',
    'children' => array(
      array(
        'id' => 1,
        'address' => 'addy 1.1',
        'children' => array(
          array(
            'id' => 1,
            'address' => 'addy 1.1.1',
          ),
        ),
      ),
    ),
  ),
  array(
    'id' => 2,
    'address' => 'addy 2',
    'children' => array(
      array(
        'id' => 1,
        'address' => 'addy 2.1'
      ),
    ),
  )
);

$out_array = makeTree($data);
print_r($out_array);

This is just a basic recursive function that performs a very similar task. It is not the full solution. Put your specific logic in there to create the final output you need, but the basic 'counter' idea you ask for works.

Hope this helps.