PHP中API如何处理数据格式和序列化

$data = array(
  "name" => "John",
  "age" => 30,
  "city" => "New York"
);

$json_data = json_encode($data);

{
  "name": "John",
  "age": 30,
  "city": "New York"
}

<book>
  <title>PHP for Beginners</title>
  <author>John Doe</author>
  <price>19.99</price>
</book>

$xml = new SimpleXMLElement('<book></book>');
$xml->addChild('title', 'PHP for Beginners');
$xml->addChild('author', 'John Doe');
$xml->addChild('price', 19.99);

echo $xml->asXML();

<book>
  <title>PHP for Beginners</title>
  <author>John Doe</author>
  <price>19.99</price>
</book>

$data = array(
  array('John', 'Doe', 30),
  array('Jane', 'Smith', 25),
  array('Bob', 'Johnson', 40)
);

$fp = fopen('file.csv', 'w');

foreach ($data as $row) {
  fputcsv($fp, $row);
}

fclose($fp);

$fp = fopen('file.csv', 'r');

while (($row = fgetcsv($fp)) !== false) {
  // 处理每一行数据
}

fclose($fp);

$data = array('name' => 'John', 'age' => 30);

$serialized_data = serialize($data);

$unserialized_data = unserialize($serialized_data);

class Person implements Serializable {
  public $name;
  public $age;

  public function serialize() {
    return serialize(array(
      'name' => $this->name,
      'age' => $this->age
    ));
  }

  public function unserialize($data) {
    $data = unserialize($data);

    $this->name = $data['name'];
    $this->age = $data['age'];
  }
}

$person = new Person();
$person->name = 'John';
$person->age = 30;

$serialized_person = serialize($person);

$unserialized_person = unserialize($serialized_person);