我认为使用trait来存储对象到数组的转换逻辑是一个不错的想法。举个简单的例子:

trait ArrayAwareTrait
{
    /**
     * Return list of Entity's parameters
     * @return array
     */
    public function toArray()
    {
        $props = array_flip($this->getPropertiesList());
        return array_map(
            function ($item) {
                if ($item instanceof \DateTime) {
                    return $item->format(DATE_ATOM);
                }
                return $item;
            },
            array_filter(get_object_vars($this), function ($key) use ($props) {
                return array_key_exists($key, $props);
            }, ARRAY_FILTER_USE_KEY)
        );
    }


    /**
     * @return array
     */
    protected function getPropertiesList()
    {
        if (method_exists($this, '__sleep')) {
            return $this->__sleep();
        }
        if (defined('static::PROPERTIES')) {
            return static::PROPERTIES;
        }
        return [];
    }
}

class OrderResponse
{
    use ArrayAwareTrait;

    const PROP_ORDER_ID = 'orderId';
    const PROP_TITLE = 'title';
    const PROP_QUANTITY = 'quantity';
    const PROP_BUYER_USERNAME = 'buyerUsername';
    const PROP_COST_VALUE = 'costValue';
    const PROP_ADDRESS = 'address';

    private $orderId;
    private $title;
    private $quantity;
    private $buyerUsername;
    private $costValue;
    private $address;

    /**
     * @param $orderId
     * @param $title
     * @param $quantity
     * @param $buyerUsername
     * @param $costValue
     * @param $address
     */
    public function __construct(
        $orderId,
        $title,
        $quantity,
        $buyerUsername,
        $costValue,
        $address
    ) {
        $this->orderId = $orderId;
        $this->title = $title;
        $this->quantity = $quantity;
        $this->buyerUsername = $buyerUsername;
        $this->costValue = $costValue;
        $this->address = $address;
    }

    /**
     * @inheritDoc
     */
    public function __sleep()
    {
        return [
            static::PROP_ORDER_ID,
            static::PROP_TITLE,
            static::PROP_QUANTITY,
            static::PROP_BUYER_USERNAME,
            static::PROP_COST_VALUE,
            static::PROP_ADDRESS,
        ];
    }

    /**
     * @return mixed
     */
    public function getOrderId()
    {
        return $this->orderId;
    }

    /**
     * @return mixed
     */
    public function getTitle()
    {
        return $this->title;
    }

    /**
     * @return mixed
     */
    public function getQuantity()
    {
        return $this->quantity;
    }

    /**
     * @return mixed
     */
    public function getBuyerUsername()
    {
        return $this->buyerUsername;
    }

    /**
     * @return mixed
     */
    public function getCostValue()
    {
        return $this->costValue;
    }

    /**
     * @return string
     */
    public function getAddress()
    {
        return $this->address;
    }
}

$orderResponse = new OrderResponse(...);
var_dump($orderResponse->toArray());

这个答案只是这篇文章的不同答案的联合，但它是将具有简单值或数组的公有或私有属性的PHP对象转换为关联数组的解决方案…

function object_to_array($obj)
{
    if (is_object($obj))
        $obj = (array)$this->dismount($obj);
    if (is_array($obj)) {
        $new = array();
        foreach ($obj as $key => $val) {
            $new[$key] = $this->object_to_array($val);
        }
    }
    else
        $new = $obj;
    return $new;
}

function dismount($object)
{
    $reflectionClass = new \ReflectionClass(get_class($object));
    $array = array();
    foreach ($reflectionClass->getProperties() as $property) {
        $property->setAccessible(true);
        $array[$property->getName()] = $property->getValue($object);
        $property->setAccessible(false);
    }
    return $array;
}

要将对象转换为数组，只需显式强制转换:

$name_of_array = (array) $name_of_object;

通过依赖JSON编码/解码函数的行为，可以快速将深度嵌套的对象转换为关联数组:

$array = json_decode(json_encode($nested_object), true);

当你从数据库中以对象的形式获取数据时，你可能想这样做:

// Suppose 'result' is the end product from some query $query

$result = $mysqli->query($query);
$result = db_result_to_array($result);

function db_result_to_array($result)
{
    $res_array = array();

    for ($count=0; $row = $result->fetch_assoc(); $count++)
        $res_array[$count] = $row;

    return $res_array;
}

下面是将PHP对象转换为关联数组的递归PHP函数:

// ---------------------------------------------------------
// ----- object_to_array_recursive --- function (PHP) ------
// ---------------------------------------------------------
// --- arg1: -- $object  =  PHP Object         - required --
// --- arg2: -- $assoc   =  TRUE or FALSE      - optional --
// --- arg3: -- $empty   =  '' (Empty String)  - optional --
// ---------------------------------------------------------
// ----- Return: Array from Object --- (associative) -------
// ---------------------------------------------------------

function object_to_array_recursive($object, $assoc=TRUE, $empty='')
{
    $res_arr = array();

    if (!empty($object)) {

        $arrObj = is_object($object) ? get_object_vars($object) : $object;

        $i=0;
        foreach ($arrObj as $key => $val) {
            $akey = ($assoc !== FALSE) ? $key : $i;
            if (is_array($val) || is_object($val)) {
                $res_arr[$akey] = (empty($val)) ? $empty : object_to_array_recursive($val);
            }
            else {
                $res_arr[$akey] = (empty($val)) ? $empty : (string)$val;
            }
            $i++;
        }
    }
    return $res_arr;
}

// ---------------------------------------------------------
// ---------------------------------------------------------

使用的例子:

// ---- Return associative array from object, ... use:
$new_arr1 = object_to_array_recursive($my_object);
// -- or --
// $new_arr1 = object_to_array_recursive($my_object, TRUE);
// -- or --
// $new_arr1 = object_to_array_recursive($my_object, 1);


// ---- Return numeric array from object, ... use:
$new_arr2 = object_to_array_recursive($my_object, FALSE);