Nested array to flat with parent_id creating - php

Question

I want to create flat array from nested array, like this one:
[0]=>Array(
"id"=>1,
"positions">Array(
[0]=>Array(
"id"=>2
),
[1]=>Array(
"id"=>3
"positions"=>Array(
[0]=>Array(
"id"=>4
)
)
)
to something like this:
[0]=>Array(
"id"=>1,
"parent_id"=>0
),
[1]=>Array(
"id"=>2,
"parent_id"=>1
),
[2]=>Array(
"id"=>3,
"parent_id"=>1
),
[3]=>Array(
"id"=>4,
"parent_id"=>3
)
I don't have parent_id in nested structure, so all the trick is to "ride" trough the nested array, and add 'parent_id', base on id from parent node. I know how to flat the array, but I need parent_id information.

Answer 1

Try below code : i hope useful it...
<?php
$array = array(array(
"id"=>1,
"positions" =>
array(
array(
"id"=>2
),
array(
"id"=>3,
"positions"=>
array(
array(
"id"=>4
)
)
)
)
));
echo "<pre>";
print_r(getArray($array));
echo "</pre>";
exit;
function getArray($array,$parent_id = 0)
{
$result = array();
foreach ($array as $value)
{
$tmp = array();
$tmp['id'] = $value['id'];
$tmp['parent_id'] = $parent_id;
$result[] = $tmp;
if(!empty($value['positions']))
{
$result= array_merge($result,getArray($value['positions'],$value['id']));
}
}
return $result;
}
?>
OUTPUT :
Array
(
[0] => Array
(
[id] => 1
[parent_id] => 0
)
[1] => Array
(
[id] => 2
[parent_id] => 1
)
[2] => Array
(
[id] => 3
[parent_id] => 1
)
[3] => Array
(
[id] => 4
[parent_id] => 3
)
)

Answer 2

Use this code
$result = array();
function generateArray($array,$parent=0){
foreach ($array as $key=>$val){
$tmp = array();
if(!empty($val['id'])){
$tmp['id'] = $val['id'];
$tmp['parent_id'] = $parent;
$result[] = $tmp;
}
if(!empty($val['positions'])){
$result=array_merge($result,generateArray($val['positions'],$val['id']));
}
}
return $result;
}
Your array must be of this structure
$data = array(0=>array("id"=>1,"positions"=>array(0=>array("id"=>2),1=>array("id"=>3,"positions"=>array(0=>array("id"=>4))))));
Then call the function generateArray(),
var_dump(generateArray($data));