引起问题的追加运算符的位置

Question

我正在尝试将对象ViewingPost附加到这些对象的数组中。当我执行此处显示的操作时，它会起作用：

     for (_,post) in snap {

                let posst = ViewingPost()

                if let totLikes = post["likes"] as? Int, let pathToImage = post["pathToImage"] as? String, let postID = post["postID"] as? String {

                    let postNum = "post" + postID

                    posst.pathToImage = pathToImage
                    posst.postID = postID
                    posst.likes = totLikes
                    self.posts.append(posst)

                    for key in 1 ... arr.count {

                        let isEq = arr[key - 1] == postNum
                        print(isEq)
                        if isEq {
                            ref.child(formattedDateD).child(postNum).observeSingleEvent(of: .value, with: { (snapsh) in
                                let snapshP = snapsh.value as! Int

                            })
                        }
                    }
                }
            }

尽管当我将其将对象附加到数组的部分移动到我想要的位置时，它仍然无法工作：

           for (_,post) in snap {

                let posst = ViewingPost()

                if let totLikes = post["likes"] as? Int, let pathToImage = post["pathToImage"] as? String, let postID = post["postID"] as? String {

                    let postNum = "post" + postID


                    for key in 1 ... arr.count {

                        let isEq = arr[key - 1] == postNum
                        print(isEq)
                        if isEq {
                            ref.child(formattedDateD).child(postNum).observeSingleEvent(of: .value, with: { (snapsh) in
                                let snapshP = snapsh.value as! Int

                                posst.pathToImage = pathToImage
                                posst.postID = postID
                                posst.likes = totLikes
                                self.posts.append(posst)
                            })
                        }
                    }
                }
            }

有人可以帮忙吗？