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);

$Menu = new Admin_Model_DbTable_Menu(); 
$row = $Menu->fetchRow($Menu->select()->where('id = ?', $id));
$Addmenu = new Admin_Form_Addmenu(); 
$Addmenu->populate($row->toArray());

对“众所周知的”代码的一些改进

/*** mixed Obj2Array(mixed Obj)***************************************/ 
static public function Obj2Array($_Obj) {
    if (is_object($_Obj))
        $_Obj = get_object_vars($_Obj);
    return(is_array($_Obj) ? array_map(__METHOD__, $_Obj) : $_Obj);   
} // BW_Conv::Obj2Array

注意，如果函数是类的成员(如上所述)，必须将__FUNCTION__更改为__METHOD__

您还可以使用Symfony Serializer组件

use Symfony\Component\Serializer\Encoder\JsonEncoder;
use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
use Symfony\Component\Serializer\Serializer;

$serializer = new Serializer([new ObjectNormalizer()], [new JsonEncoder()]);
$array = json_decode($serializer->serialize($object, 'json'), true);

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());

class Test{
    const A = 1;
    public $b = 'two';
    private $c = test::A;

    public function __toArray(){
        return call_user_func('get_object_vars', $this);
    }
}

$my_test = new Test();
var_dump((array)$my_test);
var_dump($my_test->__toArray());

输出

array(2) {
    ["b"]=>
    string(3) "two"
    ["Testc"]=>
    int(1)
}
array(1) {
    ["b"]=>
    string(3) "two"
}