Access multidimensional associative array using integer index - php

Question

Assuming I have an associative array which looks like this:
$arr = array(
'a' => array(
'b' => 'b',
'c' => 'c',
'd' => array(
'e' =>'e'
),
'f' => 'f',
'g' => 'g'
),
'h' => 'h',
'i' => array(
'j' => 'j',
'k' => 'k'
)
);
Now I want to access array elements using integer-index:
0 will return array of key 'a'
1 will return array of key 'b'
2 will return array of key 'c'
3 will return array of key 'd'
4 will return array of key 'e'
..
11 will return array of key 'k'
I have tried to accomplish this by recursion using the following code:
function getElement($arr, $id)
{
static $counter = 0;
foreach($arr as $key => $val){
$varNum = count($val);
$total = $counter + $varNum;
if($counter == $id){
return $val;
}
elseif($total > $id){
$counter++;
$res = getElement($val, $id);
return $res;
}
$counter++;
}
}
However from index 4 the function fails.
any suggestions?

Answer 1

Using array_walk_recursive:
$list = [];
array_walk_recursive($arr, function($value) use (&$list) {
$list[] = $value;
});
print_r($list);
Will return something like:
Array
(
[0] => b
[1] => c
[2] => e
[3] => f
[4] => g
[5] => h
[6] => j
[7] => k
)
now to return a full list of keys , you may use the following function:
function walk_recursive($arr, &$list = [])
{
foreach ($arr as $k => $ar) {
if (is_array($ar)) {
$list[] = $k;
walk_recursive($ar, $list);
} else {
$list[] = $ar;
}
}
return $list;
}
print_r(walk_recursive($arr));
this output the following :
Array
(
[0] => a
[1] => b
[2] => c
[3] => d
[4] => e
[5] => f
[6] => g
[7] => h
[8] => i
[9] => j
[10] => k
)
live example: https://3v4l.org/Wv0nL