Transform Multiple arrays into an array only

Question

In certain process of my system, I receive as return of a function a array of characteristics and that array may contain various information, including other information arrays with different names for each type of information. Ex:

Apartamento:
Characteristics => [
 ["external_area"]=>
    array(5) {
      [0]=> "varanda"
      [1]=> "lavanderia"
      [2]=> "piscina"
      [3]=> "muros"
      [4]=> "area_serviço"
    }
    ["bedroom"]=>
     array(12) {
      [0]=> "piso_frio"
      [1]=> "alvenaria"
      [2]=> "azulejo_teto"
      [3]=> "massa_corrida"
      }
   ]

Casa:
Characteristics => [
 ["internal_area"]=>
    array(5) {
      [0]=> "mesa de madeira"
      [1]=> "area"
    }
    ["options"]=>
     array(12) {
      [0]=> "2 andares"
      [1]=> "banheiro externo"
      }
   ]

and I need everything to stay inside an array only, for example apartment, would be:

Characeristics => [
   [0]=> "varanda"
   [1]=> "lavanderia"
   [2]=> "piscina"
   [3]=> "muros"
   [4]=> "area_serviço"
   [5]=> "piso_frio"
   [6]=> "alvenaria"
   [7]=> "azulejo_teto"
   [8]=> "massa_corrida"
]

EDIT: Remembering that I don’t know the names of arrays that comes within Characteristics

Answer 1

Once I needed it and used it this solution.

function flatten($array) {
    $return = array();
    array_walk_recursive($array, function($a) use (&$return) { $return[] = $a; });
    return $return;
}

This way works independent of the number of subarrays you have and also independent of keys. Ex.: https://eval.in/671144

Answer 2

You can use the function array_walk_recursive:

array_walk_recursive($array, function ($item, $key) 
{
    global $Characeristics;
    if (! is_array( $item ) ) $Characeristics[] = $item;
});

$result = array( "Characeristics" => $Characeristics );

That is, if the value you are currently passing is not an array (it will be your feature string) it is added to a new array.

The ideone is working

Answer 3

Example of how you can do it:

$arr = array(
    0 => array(1, 2, 3),
    1 => array(4, 5, 6)
);

$rs = array();
foreach ($arr as $v) {
    $rs = array_merge($rs, array_values($v));
}
unset($arr);

print_r($rs);

Be aware that this is an example. The original question array has an extra level, however, it can solve with the same logic.

In your case it must look something like this:

$rs = array('Characteristics' => array()); // Esse array serve para guardar o resultado final

foreach ($arr['Characteristics']['external_area'] as $v) {
    //aqui mescla os valores
    $rs['Characteristics'] = array_merge($rs, array_values($v));
}
unset($arr); // Se não precisar mais desses dados, apague-os

print_r($rs);

Key names

If the name of the first key is unknown, you can get it with the key function()

$arr['a']['b'] = array();
echo key($arr['a']);
// retorna 'b'

For your specific case:

$arr['Characteristics']['external_area'] = array();
echo key($arr['Characteristics']);
// retorna 'external_area'

Implementing in sample code

$rs = array('Characteristics' => array()); // Esse array serve para guardar o resultado final

$k = key($arr['Characteristics']); // obtém o nome da primeira chave

foreach ($arr['Characteristics'][$k] as $v) {
    //aqui mescla os valores
    $rs['Characteristics'] = array_merge($rs, array_values($v));
}
unset($arr); // Se não precisar mais desses dados, apague-os

print_r($rs);

Answer 4

I developed a function that goes through the array and merges the array, take a look, I considered the array $characteristics as the first one you posted on the question, I hope it helps

var_dump(getAllCharacteristics($characteristics));
die;

function getAllCharacteristics($characteristics) {
    $newArray = [];
    foreach ($characteristics as $characteristic) {
        if (is_array($characteristic)) {
            $newArray = array_merge($newArray, getAllCharacteristics($characteristic));
        } else {
            $newArray[] = $characteristic;
        }
    }
    return $newArray;
}

The output of the function var_dump would be:

array(9) {
  [0]=>
  string(7) "varanda"
  [1]=>
  string(10) "lavanderia"
  [2]=>
  string(7) "piscina"
  [3]=>
  string(5) "muros"
  [4]=>
  string(13) "area_serviço"
  [5]=>
  string(9) "piso_frio"
  [6]=>
  string(9) "alvenaria"
  [7]=>
  string(12) "azulejo_teto"
  [8]=>
  string(13) "massa_corrida"
}