探索PHP内置对象的功能：了解PHP提供了哪些内置对象

$person = new stdClass();
$person->name = 'John Doe';
$person->age = 30;
$person->getInfo = function () use ($person) {
    echo "Name: {$person->name}, Age: {$person->age}";
};

$person->getInfo(); // 输出：Name: John Doe, Age: 30

$now = new DateTime();
echo $now->format('Y-m-d'); // 输出当前日期，例如：2022-01-01

$birthday = new DateTime('1990-01-01');
$age = $now->diff($birthday)->y;
echo "Age: {$age}"; // 输出：Age: 32

$fruits = new ArrayObject(['apple', 'banana', 'orange']);
$fruits->append('kiwi');
$fruits->offsetUnset(1);

foreach ($fruits as $fruit) {
    echo $fruit . ', '; // 输出：apple, orange, kiwi,
}

function divide($dividend, $divisor) {
    if ($divisor == 0) {
        throw new Exception('Divisor cannot be zero');
    }

    return $dividend / $divisor;
}

try {
    $result = divide(10, 0);
    echo "Result: {$result}";
} catch (Exception $e) {
    echo "Error: {$e->getMessage()}"; // 输出：Error: Divisor cannot be zero
}

$dsn = 'mysql:host=localhost;dbname=test';
$user = 'root';
$pass = 'password';

try {
    $pdo = new PDO($dsn, $user, $pass);
    $stmt = $pdo->query('SELECT * FROM users');

    while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
        echo $row['name'] . ', '; // 输出：John Doe, Jane Smith, ...
    }
} catch (PDOException $e) {
    echo "Error: {$e->getMessage()}";
}