php如何返回mysql数据

<?php
try {
    // 数据库连接配置
    $host = 'localhost';
    $db   = 'test';
    $user = 'root';
    $pass = '';
    $charset = 'utf8mb4';

    // 创建PDO实例
    $dsn = "mysql:host=$host;dbname=$db;charset=$charset";
    $options = [
        PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
        PDO::ATTR_EMULATE_PREPARES   => false,
    ];
    $pdo = new PDO($dsn, $user, $password, $options);

    // 执行查询
    $sql = "SELECT * FROM users";
    $stmt = $pdo->query($sql);

    // 获取结果
    $users = $stmt->fetchAll();

    // 输出结果
    foreach ($users as $user) {
        echo "ID: " . $user['id'] . " - Name: " . $user['name'] . "<br>";
    }
} catch (\PDOException $e) {
    throw new \PDOException($e->getMessage(), (int)$e->getCode());
}
?>