我的图形请求不断出现此错误？

输入“是吗？” 没有下标成员

错误指向结果…。这仅在我转换为Swift 3时发生了…有人吗？？？？

 let nextrequest: FBSDKGraphRequest = FBSDKGraphRequest(graphPath: "me/friends", parameters: ["fields": "name, id, gender"], httpMethod: "GET")
            nextrequest.start { (connection, result, error) -> Void in
                guard let listOfFriends = result["data"] as? [AnyObject] else {
                    return
                }
            }
        }