在PHP中将类的静态成员编码为JSON

Question

I have the following piece of code.

class SomeClass
{
    public static $one = 1;
    private static $two = 2;
    public $three = 3;
    private $four = 4;
}

header("Content-Type: application/json");
echo json_encode(new SomeClass());

What I want to achieve is encode the public class property and member as a JSON object. My problem is that json_encode() ignores public static $one = 1; and the result will be:

{
    "three": ​3
}

Although I expect it to print the public static member as well, such as:

{
    "one": 1,
    "three": ​3
}

Can JSON encoding be done with static members in PHP?

Answer 1

According to PHP manual:

Static properties cannot be accessed through the object using the arrow operator ->.

That means no

Nevertheless, I came up with the solution utilizing Reflections:

class SomeClass
{
    public static $one = 1;
    private static $two = 2;
    public $three = 3;
    private $four = 4;
}

$reflection = new ReflectionClass('SomeClass');
$instance = $reflection->newInstance();
$properties = $reflection->getProperties(ReflectionProperty::IS_PUBLIC);

$jsonArray = array();

foreach($properties as $property) {
    $jsonArray[$property->getName()] = $property->getValue($instance);
}

echo json_encode($jsonArray);

The result is

{"one":1,"three":3}