将PHP数组从mysql转换为JSON格式

$servername = "数据库服务器地址";
$username = "用户名";
$password = "密码";
$dbname = "数据库名";

$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

$sql = "SELECT id, name FROM users";
$result = $conn->query($sql);

$data = array();

while ($row = $result->fetch_assoc()) {
    $data[] = $row;
}

$jsonData = json_encode($data);

$conn->close();