json_encode function not return Braces {} when array is empty in php

use the JSON_FORCE_OBJECT option of json_encode:

json_encode($status, JSON_FORCE_OBJECT);

Documentation

JSON_FORCE_OBJECT (integer)
Outputs an object rather than an array when a non-associative array is used. Especially useful when the recipient of the output is expecting an object and the array is empty. Available since PHP 5.3.0.

Or, if you want to preserve your “other” arrays inside your object, don’t use the previous answer, just use this:

$status = array(
                "message"=>"error",
                "club_id"=>$_club_id,
                "status"=>"1",
                "membership_info"=> new stdClass()
                );