Generate multidimensional array based on given array - php

Question

I have an array say,
$arr = ["x", "y", "z"];
What I want to achieve is create another array based on given array such as
$arr1["x" =>["y" => ["z"]]] = "some value";
Any idea to achieve this? Thanks in advance.
Edited:
'some value' is just a dummy data. What I'm trying to achieve is the multidimensional structure.

Answer 1

You can recursively build an array, taking and removing the first element of an array on each call :
function buildArray($arr, $someValue)
{
if (count($arr) == 0)
return $someValue;
// the key is the first element of the array,
// removed and returned at the same time using array_shift()
return [ array_shift($arr) => buildArray($arr, $someValue) ];
}
$arr = ["x", "y", "z"];
$arr1 = buildArray($arr, "some value");
var_dump($arr1);
echo "------------------------" . PHP_EOL;
// note that $arr is preserved
var_dump($arr);
This outputs :
array(1) {
["x"]=>
array(1) {
["y"]=>
array(1) {
["z"]=>
string(10) "some value"
}
}
}
------------------------
array(3) {
[0]=>
string(1) "x"
[1]=>
string(1) "y"
[2]=>
string(1) "z"
}

Answer 2

$keys = array('key1', 'key2', 'key3');
$value = 'some value';
$md = array();
$md[$keys[count($keys)-1]] = $value;
for($i=count($keys)-2; $i>-1; $i--)
{
$md[$keys[$i]] = $md;
unset($md[$keys[$i+1]]);
}
print_r($md);

Answer 3

You need to create recursive function:
function rec_arr($ar, $val){
$res = [];
if(is_array($ar) && count($ar)>0){
$tmp = $ar[0]; // catching the first value
unset($ar[0]); // unset first value from given array
sort($ar); // makes indexes as 0,1,...
$res[$tmp] = rec_arr($ar, $val); // recursion
} else {
return $val; // passing value to the last element
}
return $res;
}
Demo
Outputs:
Array
(
[x] => Array
(
[y] => Array
(
[z] => some value
)
)
)