我有一些类似于here.

在第三方插件类中，我们有一个函数，我想通过扩展该类来覆盖它。

原始类函数：

class Import_Facebook_Events_Facebook {
    public function get_location( $facebook_event ) {

        if ( !isset( $facebook_event->place->id ) ) {
            return null;
        }
        //other code here
}

我尝试了什么，但没有成功（没有效果）：

class Import_Facebook_Events_Facebook_Ext extends Import_Facebook_Events_Facebook {
    public function get_location( $facebook_event ) {

        if ( !isset( $facebook_event->place->id ) ) {
            $facebook_event->place->id = \'\'; //added this line
            //return null;
        }
        //other code here
}

new Import_Facebook_Events_Facebook_Ext();

What\'s wrong here? How can I get the desired effect?

原件Import_Facebook_Events_Facebook() 类是从另一个类实例化的：

class Import_Facebook_Events{

    private static $instance;

    public static function instance() {
        if( ! isset( self::$instance ) && ! (self::$instance instanceof Import_Facebook_Events ) ) {
            self::$instance = new Import_Facebook_Events;

            self::$instance->facebook = new Import_Facebook_Events_Facebook();

        }
        return self::$instance; 
    }
}

上述类是从单独的函数实例化的：

function run_import_facebook_events() {
    return Import_Facebook_Events::instance();
}

class Import_Facebook_Events_Facebook_Ext extends Import_Facebook_Events_Facebook {

    function get_location( $facebook_event ) {

        if ( !isset( $facebook_event->place->id ) ) {
            $facebook_event->place->id = \'\';
            //return null;
        }
        //other code here

        return $event_location;
    }
}

$new_ife_events = run_import_facebook_events();
$new_ife_events->facebook = new Import_Facebook_Events_Facebook_Ext();