Firebase - 如何获取observeEventType = Value 中的键值 [英] Firebase - how to get the key value in observeEventType = Value

问题描述

这是Firebase - 构建数据库的正确方法的后续问题

我有以下数据库结构:

"artists" : {
  "-KKMkpA22PeoHtBAPyKm" : {
    "name" : "Skillet"
  }
}

我想查询艺术家参考，看看艺术家是否已经在数据库中，如果艺术家在数据库中，获取艺术家密钥(在上面的例子中它是 -KKMkpA22PeoHtBAPyKm).

And I want to query the artists ref and see if an artist is already in the DB or not and if the artist IS in the DB, get the artist key (in the above example it would be -KKMkpA22PeoHtBAPyKm).

我试过了:

artistsRef.queryOrderedByChild("name").queryEqualToValue("Skillet").observeEventType(.Value, withBlock: { (snapshot) in
        if snapshot.exists() {
            print("we have that artist, the id is (snapshot.key)")
        } else {
            print("we don't have that, add it to the DB now")
        }
    })

但是snapshot.key"只给了我艺术家"的父键.

but "snapshot.key" only gives me the parent key which is "artists".

我怎样才能得到我需要的钥匙?

How can I get the key I need?

推荐答案

在if条件下，需要获取allKeys才能得到-KKMkpA22PeoHtBAPyKm"...

In if condition, you need to get allKeys to get "-KKMkpA22PeoHtBAPyKm" ...

    if snapshot.exists() {
        for a in (snapshot.value?.allKeys)!{
            print(a)
        }
    } else {
        print("we don't have that, add it to the DB now")
    }

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