如何向paypal沙箱发送税和运费？

Question

这是我的代码： 这段代码允许我添加费率和数量到paypal，但税和运费似乎是不可能我添加。

所以，请帮我解决这个问题。 告诉我，如果在codeigniter中有一些库，或者我必须修改这段代码吗？

public function do_purchase()
            {



$config['business'] = 'stars_1336125903_biz@a1professionals.com'; //Your PayPal account
                    $config['cpp_header_image']     = ''; //Image header url [750 pixels wide by 90 pixels high]
                    $config['return']               = base_url().'front/payment/notify_payment';
                    $config['cancel_return']        = base_url().'front/payment/cancel_payment';
                    $config['notify_url']           = base_url().'front/payment/notify_payment';
                    $config['production']           = FALSE; //Its false by default and will use sandbox

                    $config["shipping"] = 10;
                    $config["shipping2"] = 10;
                    $config["handling"] = 10;
                    $config["tax1"] = 10;
                    $config["invoice"]              = $this->inv; //The invoice id


                                    $config["first_name"] = $this->input->post('firstname');
                                    $config["last_name"] = $this->input->post('lastname');
                                    $config["address1"] = $this->input->post('address1');
                                    $config["address2"] = $this->input->post('address2');
                                    $config["country"] = $this->input->post('country');
                                    $config["state"] = $this->input->post('state');
                                    $config["city"] = $this->input->post('city');
                                    $config["zip"] = $this->input->post('postalcode');
                                    $config["email"] = 'testerone@a1professionals.com';
                                    //To save shipping add

                                    $this->load->library('paypal',$config);
                                    foreach ($this->cart->contents() as $items)
                                        {
                                            #$this->paypal->add(<name>,<price>,<quantity>[Default 1],<code>[Optional]);
                                            $this->paypal->add($items['name'],$items['price'],$items['qty'],$items['id']); //First item
                                        }
                                    $this->paypal->pay(); //Proccess the payment
            }