Problems with JSON + PHP

Question

I have a file JSON which is being used to store settings, and a file php, which reads and fills the file according to the data reported, however after the settings are edited for many times the JSON is has its format changed from Array for Object:

Format required:

{"favoritesIndex":[28,22,133,38,12,27]}

Generated format:

{"favoritesIndex":{"1":28,"2":22,"3":133,"4":38,"5":12,"6":27}}

PHP code:

function read() {return json_decode(file_get_contents('sec_settings/datatable.json'));}
function write($data){return file_put_contents('sec_settings/datatable.json',json_encode($data));}

function setFavorite()
{
    $settings = read();
    $settings->favoritesIndex[] = (int) $_REQUEST['id'];
    $settings = write($settings);
}

function removeFavorite()
{
    $settings = read();

    foreach($settings->favoritesIndex AS $key => $value)
        if($_REQUEST['id'] == $value)
            unset($settings->favoritesIndex[$key]);

    $settings = write($settings);
}

try
{
    if(isset($_REQUEST['fn'])) $_REQUEST['fn']();
}
catch(Exception $e)
{
    die("Could not process requested operation, {$e}");
}

Answer 1

I believe this occurs when Dexes cease to be sequential, so it is necessary to be an object to continue with the same Dexes.

For example consider this:

$json = json_decode('{"favoritesIndex":[28,22,133,38,12,27]}');

unset($json->favoritesIndex[5]);

echo json_encode($json);

The return will be {"favoritesIndex":[28,22,133,38,12]}, why the 5 is the ultimate value, so it still remains 0 until 4.

However, if you remove anyone other than the last:

$json = json_decode('{"favoritesIndex":[28,22,133,38,12,27]}');

unset($json->favoritesIndex[1]); // Remover o 22, o segundo valor

echo json_encode($json);

You will create a gap (existing value 0 and 2 until 5), so it will result {"favoritesIndex":{"0":28,"2":133,"3":38,"4":12,"5":27}}, due to the lack of 1, that was removed.

---

Then you need to recreate the PHP array, so that it is always in order, without any gap, this can be done as follows:

$settings['favoritesIndex'] = array_values($settings['favoritesIndex']);

In case there would be any next to that:

function read() {return json_decode(file_get_contents('sec_settings/datatable.json'), true);}
function write($data){return file_put_contents('sec_settings/datatable.json',json_encode($data));}


function setFavorite(int $valor)
{
    $settings = read();
    $settings['favoritesIndex'][] = $valor;
    $settings = write($settings);
}

function removeFavorite(int $valor)
{
    $settings = read();

    $achado = array_search($valor, $settings['favoritesIndex']);
    if($achado !== false){
        unset($settings['favoritesIndex'][$achado]);
    }

    $settings['favoritesIndex'] = array_values($settings['favoritesIndex']);

    $settings = write($settings);
}

Note that there are changes (how to use array with the json_decode(..., true), the value is reported as a parameter in the function...), this was done only so that it could test faster, as you can see here working.

Answer 2

It is putting a natural input in the array, and you are trying to access a key that is not key, wrong method:

function setFavorite()
{
    $settings = read();
    //Essa abertura [] indica para preencher o indice de acordo com o loop e gera uma chave sequencial
    $settings->favoritesIndex[] = (int) $_REQUEST['id'];
    $settings = write($settings);
}

Do this by making the Intel your own value:

function setFavorite()
{
    $settings = read();
    $ID = (int) $_REQUEST['id'];

    $settings->favoritesIndex[$ID];
    $settings = write($settings);
}

I believe this will solve, only the positions in the array construction are wrong.