Question

root
  |
  @--reviews
        |
        |
        @--postABC // postId
               |
               |
               @--reviewXYZ // ***I want everything under this reviewUID
               |    |
               |    |--buyerUID: "01010"
               |    |--text: "fast shipping!"
               |    |
               |    @--responseTUV // responseUID
               |         |
               |         |--sellerUID: "212555"
               |         |--text: "we aim to please"
               |     
               @--reviewEFG // this review is from a totally different user I don't want anything from here

我的数据库如上所述进行设置。有时我只有买家uid，因此我使用.queryOrdered(byChild: "buyerUID").queryEqual(toValue: "01010")提取数据，然后可以从该特定帖子及其评论中找到买家。

找到他们后，如何获取与该节点（reviewXYZ）下的买方关联的所有其他k / v？

let reviewsRef = Database.database().reference()?
                   .child("reviews")
                   .child("postABC")
                   .queryOrdered(byChild: "buyerUID")
                   .queryEqual(toValue: "01010")

reviewsRef?.observeSingleEvent(of: .value, with: { [weak self](snapshot) in

    print(snapshot.key) // prints  postABC
    print(snapshot.value) // prints a dictionary with reviewXYZ as the key and everything underneath it as a value

    guard let dict = snapshot.value as? [String: Any] else { return }
})

Answer 1

DataSnapshot class具有内置方法来循环其子级。

reviewsRef?.observeSingleEvent(of: .value, with: { [weak self](snapshot) in
  for child in snapshot.children {
    let snap = child as! DataSnapshot;
    print(snap.key)
    print(snap.value) 
    print(snap.childSnapshot(forPath: "buyerUID").value)
  }
})

另请参见其他search results for looping over Firebase child nodes in Swift。

Swift Firebase-如何在使用queryOrdered（byChild：）.queryEqual（toValue：）

1 个答案: