How to initialize an empty associative array in PHP?

Question

I want to have an empty object in the API response like the one mentioned below:

{
  "sample" : {}
}

When I assign $response['sample'] = array(), I get the following response

{
  "sample" : []
}

Answer 1

{}表示一个对象，因此您必须使用

$result = ["sample" => new stdclass()];

Answer 2

you must try JSON_FORCE_OBJECT as second argument while using json_encode function.

EDIT

$ar = array("sample" => array());
echo json_encode($ar, JSON_FORCE_OBJECT);