php - String with array structure to Array

Question

This question already has answers here:

Answer 1

Given the values

$key = "Main.Sub.SubOfSub";
$target = array();
$value = "SuperData";

Here's some code I have lying around that does what you need1:

$path = explode('.', $key);
$root = &$target;

while(count($path) > 1) {
    $branch = array_shift($path);
    if (!isset($root[$branch])) {
        $root[$branch] = array();
    }

    $root = &$root[$branch];
}

$root[$path[0]] = $value;

See it in action.

1 Actually it does slightly more than that: it can be trivially encapsulated inside a function, and it is configurable on all three input values (you can pass in an array with existing values, and it will expand it as necessary).