How can I check if a PHP object is empty (i.e. has no properties)? The built-in empty() does not work on objects according the doc:
5.0.0 Objects with no properties are no longer considered empty.
http://www.php.net/manual/en/reflectionclass.getproperties.php
class A {
public $p1 = 1;
protected $p2 = 2;
private $p3 = 3;
}
$a = new A();
$a->newProp = '1';
$ref = new ReflectionClass($a);
$props = $ref->getProperties();
// now you can use $props with empty
echo empty($props);
print_r($props);
/* output:
Array
(
[0] => ReflectionProperty Object
(
[name] => p1
[class] => A
)
[1] => ReflectionProperty Object
(
[name] => p2
[class] => A
)
[2] => ReflectionProperty Object
(
[name] => p3
[class] => A
)
)
*/
Note that newProp is not returned in list.
http://php.net/manual/en/function.get-object-vars.php
Using get_object_vars will return newProp, but the protected and private members will not be returned.
So, depending on your needs, a combination of reflection and get_object_vars may be warranted.
I believe (not entirely sure) that you can override the isset function for objects.
In the class, you can provide an implemention of __isset() and have it return accordingly to which properties are set.
Try reading this: http://www.php.net/manual/en/language.oop5.overloading.php#language.oop5.overloading.members