如何使用php组合JSON对象？

$data = array(
    "name" => "John Doe",
    "age" => 30,
    "email" => "johndoe@example.com"
);

$jsonData = json_encode($data);

$jsonData = json_encode($data, JSON_PRETTY_PRINT);

$data = array(
    "name" => "John Doe",
    "age" => 30,
    "email" => "johndoe@example.com"
);

$jsonData = json_encode($data, JSON_PRETTY_PRINT);

echo $jsonData;

{
    "name": "John Doe",
    "age": 30,
    "email": "johndoe@example.com"
}