Recursively loop through multidimensional to create flat array

Question

I have a multidimensional array that looks like this:

$trees = array(
    array(
        \'name\' => \'Parent\',
        \'__children\' => array(
                  


        

Answer 1

Ok I have given this a shot and although it might not be the cleanest solution I think it should get the job done:

function flattenRecursive(array &$flat, $parentkey, array $nested){

    $flag       = true;
    $prepend    = '';

    foreach( $nested as $k => $val ){
        if( is_array($val) ){

            if ( $k == '__children' && $flag) {
                $prepend = end($flat);
                $flag = true;
            } else {
                $flag = false;
            }

            flattenRecursive($flat, $prepend , $val);

        } else {

            $flat[] = $parentkey . ' ' . $val;

        }
    }
}

function flatten(array $nested){
    $flat = array();
    flattenRecursive($flat, '', $nested);
    return $flat;
}

On a test array (with extra nesting for extra testing) as follows

$trees = array(
            array(
                'name' => 'Parent',
                '__children' => array(
                    array(
                        'name' => 'Child',
                        '__children' => array(
                            array(
                                'name' => 'Nest One'
                            ),
                            array(
                                'name' => 'Nest Two'
                            )
                        )
                    ),
                    array(
                        'name' => 'Second Child'
                    )
                )
            )
        );

$result = flatten($trees);

the var_dump of $result looks like the following

array(5) {
  [0]=>
  string(7) " Parent"
  [1]=>
  string(13) " Parent Child"
  [2]=>
  string(22) " Parent Child Nest One"
  [3]=>
  string(22) " Parent Child Nest Two"
  [4]=>
  string(20) " Parent Second Child"
 }

Hopefully this was what you were looking for