PHP: Building multidimensional array - php

Question

I have an array like this:
Array(
'level1' => 'someval',
'level2' => 'someotherval',
'level3' => 'thirdval'
)
I want to turn it into this:
Array(
'someval' => Array(
'someotherval' => Array(
'thirdval' => 1
)
)
)
Obviously I could build the example above by hand but I don't know how many levels there will be. And this simple example might seem useless, but there are going to be more values, so there will be multiple arrays inside each of the levels.

Answer 1

This will do it
$array = array(
'level1' => array(
'level2' => array(
'level3' => 1
)
)
);

Answer 2

Here's my take on it:
function make_multi_level_array($arr) {
if (count($arr) == 1) return array(array_pop($arr) => 1);
else {
$level_key = array_pop(array_reverse($arr));
$sub_level = make_multi_level_array(
array_slice($arr,1,count($arr)-1)
);
return array(
$level_key => $sub_level
);
}
}
$arr = array(
'level1' => 'someval',
'level2' => 'someotherval',
'level3' => 'thirdval',
);
var_dump(make_multi_level_array($arr));
Will output this:
array(1) {
["someval"]=>
array(1) {
["someotherval"]=>
array(1) {
["thirdval"]=>
int(1)
}
}
}
Also tried other cases like below.
$arr = array(
'level1' => 'someval',
'level2' => 'someotherval',
'level3' => 'thirdval',
'level4' => 'fourthval'
);
Seems okay:
array(1) {
["someval"]=>
array(1) {
["someotherval"]=>
array(1) {
["thirdval"]=>
array(1) {
["fourthval"]=>
int(1)
}
}
}
}

Answer 3

Do you need something like this?
$levels = array_keys(Array(
'level1' => 'someval',
'level2' => 'someotherval',
'level3' => 'thirdval'
));
$array = Array();
$aux = &$array;
foreach ($levels as $level => $value) {
if ($aux == 1)
$aux = array($value => 1);
$aux = &$aux[$value];
}
var_dump($array);