converting a delineated string into an array path in PHP - php

Question

I'd appreciate any help I could get with this — I've been scouring stack overflow and couldn't find anything that directly related with what I'm trying to accomplish.
Issue: I'm trying to update a specific name/value pair in a JSON file, and I'm trying to do it by sending specific parameters through an AJAX call to a PHP file. Two of the parameters are the path (delineated with hyphens) to the name, and the value that I'm swapping in.
A small portion of the JSON:
{
"character" :
{
"name" : "Foo",
"species" : "Bar",
}
}
Using this JSON as an example, I'm trying to update a specific array value, such as:
$char['character']['name']
I'm passing a variable to the PHP file with the path information, such as:
updater.php?char=character-name&val=Newname
Is there a way to convert the string "character-name" (or any string for that matter with a particular delineation) to the path in an Array, like $char['character']['name']?

Answer 1

$array = explode("-", $_GET['char']);
$char=json_decode(....); //your json string
$char[$array[0]][$array[1]]=$_GET['val'];

Answer 2

To not only read the value at the specified path, but also update the json, I would suggest something like
<?php
function json_replace_path($json, $path, $newValue)
{
$json = json_decode($json);
$pathArray = explode('-', $path);
$currentElement = $json;
foreach ($pathArray as $part)
{
$currentElement = &$currentElement->$part;
}
$currentElement = $newValue;
return json_encode($json);
}
$json = '{"character":{"name":"Foo","species":"Bar","other":{"first_name":"Jeff","last_name":"Atwood"}}}';
echo json_replace_path($json, 'character-name', 'new name') . "\n";
echo json_replace_path($json, 'character-species', 'new species') . "\n";
echo json_replace_path($json, 'character-other-last_name', 'Bridges') . "\n";
Does not support JSON including arrays, though.

Answer 3

Something like that should work, I guess :
$a = explode("-", $_GET['char']);
$array = ...; //Your json array here
while (is_array($array) && count($a) > 0)
{
$array = $array[array_shift($a)];
}

Answer 4

Why not just use updater.php?character[name]=Newname? Then you can get it with:
echo $_GET['character']['name'];
Makes much more sense. Why concatenate things and then try and separate them into an array when you can just use an array from the start?