从第一个谷歌点击“PHP对象到assoc数组”，我们有:

function object_to_array($data)
{
    if (is_array($data) || is_object($data))
    {
        $result = [];
        foreach ($data as $key => $value)
        {
            $result[$key] = (is_array($value) || is_object($value)) ? object_to_array($value) : $value;
        }
        return $result;
    }
    return $data;
}

来源是codesnippets.joyent.com。

与json_decode和json_encode的解决方案相比，这个解决方案似乎更快。下面是一个随机的基准测试(使用简单的时间测量):

$obj = (object) [
    'name'    =>'Mike',
    'surname' =>'Jovanson',
    'age'     =>'45',
    'time'    =>1234567890,
    'country' =>'Germany',
];

##### 100 000 cycles ######
* json_decode(json_encode($var))   : 4.15 sec
* object_to_array($var)            : 0.93 sec

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);

自定义函数将stdClass转换为数组:

function objectToArray($d) {
    if (is_object($d)) {
        // Gets the properties of the given object
        // with get_object_vars function
        $d = get_object_vars($d);
    }

    if (is_array($d)) {
        /*
        * Return array converted to object
        * Using __FUNCTION__ (Magic constant)
        * for recursive call
        */
        return array_map(__FUNCTION__, $d);
    } else {
        // Return array
        return $d;
    }
}

另一个将Array转换为stdClass的自定义函数:

function arrayToObject($d) {
    if (is_array($d)) {
        /*
        * Return array converted to object
        * Using __FUNCTION__ (Magic constant)
        * for recursive call
        */
        return (object) array_map(__FUNCTION__, $d);
    } else {
        // Return object
        return $d;
    }
}

使用的例子:

// Create new stdClass Object
$init = new stdClass;

// Add some test data
$init->foo = "Test data";
$init->bar = new stdClass;
$init->bar->baaz = "Testing";
$init->bar->fooz = new stdClass;
$init->bar->fooz->baz = "Testing again";
$init->foox = "Just test";

// Convert array to object and then object back to array
$array = objectToArray($init);
$object = arrayToObject($array);

// Print objects and array
print_r($init);
echo "\n";
print_r($array);
echo "\n";
print_r($object);

转换和删除烦人的星星:

$array = (array) $object;
foreach($array as $key => $val)
{
    $new_array[str_replace('*_', '', $key)] = $val;
}

也许，它会比使用反射更便宜。

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);

由于很多人发现这个问题是因为在动态访问对象属性时遇到了麻烦，我只想指出，你可以在PHP中这样做:

在上下文(删除HTML输出可读性):

$valueRows = json_decode("{...}"); // Rows of unordered values decoded from a JSON object

foreach ($valueRows as $valueRow) {

    foreach ($references as $reference) {

        if (isset($valueRow->{$reference->valueName})) {
            $tableHtml .= $valueRow->{$reference->valueName};
        }
        else {
            $tableHtml .= " ";
        }
    }
}