发送Json作为回调

Question

我是Swift的新手，我正在尝试将我的帖子结果发送给另一个班级 这是我的帖子功能：

static func SetOrder(Json json : String , 
callback:@escaping (_ state:Int ,_ order : [Order])->Void){

let uri = ORDER + Auth(index: 1)
NetworkConnection.postData(Url: uri, Json: json) { (respone, state) in
    if state == 1 {
           callback( 1, [respone as! Order])
    } else {
        callback(0 , [respone as! Order] )
    } } }

这是我想要使用我的结果的类：

Order.SetOrder(Json: orderJson as! String, callback: { (state , json) in
    if state == 1 {
        if self.order.payment_method == "something" {
            print("this is order")
            print(json)

            //===== if cashier on Net ====================
            var URlToPayment = getCheckoutUrl(OrderNumber: json.id 
              ,OrderKey:  json.order_key)
             GO TO PEYMEnt
            let url:NSURL? = NSURL(string:"\(URlToPayment)")
            UIApplication.shared.openURL(url! as URL)
        } 
    }
})