String to array

gistfile1.php

<?php
function stringToArray($key)
{
    $result  = array();
    $parts   = explode('.', $key);
    $current = &$result;

    for ($i = 0, $max = count($parts); $i < $max; $i++) {
        if (!isset($current[$parts[$i]])) {
            $current[$parts[$i]] = array();
        }

        if ($max == ($i+1)) {
            $current[$parts[$i]] = 1;
        }

        $current = &$current[$parts[$i]];
    }

    return $result;
}

# input: This.Is.A.Test
# output: Array ( 
#    [This] => Array ( 
#        [Is] => Array ( 
#            [A] => Array ( 
#                [Test] => 1 
#            ) 
#        ) 
#    ) 
#)