Code
<?php
declare(strict_types=1);
// Array → JSON
$data = ['name' => 'Anna', 'roles' => ['admin', 'editor']];
$json = json_encode($data, JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR);
// JSON → Array
$input = '{"user":"Ben","alter":32}';
$parsed = json_decode($input, associative: true, flags: JSON_THROW_ON_ERROR);
echo $parsed['user']; // Ben
Ben