arrays - 从数组值中查找 Firebase Child - xcode 8/swift 3

Question

如果 snapshot.value 是“pending”，我想获取一个以 snapshot.key 作为 UID 的快照。将其存储到数组中。然后我想遍历 UID 数组并从 .child("users") 中提取所有详细信息，即“电子邮件”、“姓名”和“profileURL”。不确定这里的最佳路线是什么。我是将快照存储到字典中，然后将字典过滤为“待定”，还是在快照调用本身中执行此操作？

我的 Firebase 数据库中的 friend 和用户 JSON 结构(如下；)

{
  "friends" : {
    "YPQYLtXnMbbmFugrJJPYe6rOIJg2" : {
      "Z6PnyFKSR9MBMd9dfCEs0VMIOog2" : "pending"
    },
    "Z6PnyFKSR9MBMd9dfCEs0VMIOog2" : {
      "YPQYLtXnMbbmFugrJJPYe6rOIJg2" : "pending",
      "ZyAV7PH4VHWnLyWrWaZty5C9RWT2" : "pending",
      "lNI9FxCErqMUNiW43yiDpkNoljg1" : "pending"
    },
    "ZyAV7PH4VHWnLyWrWaZty5C9RWT2" : {
      "Z6PnyFKSR9MBMd9dfCEs0VMIOog2" : "pending"
    },
    "lNI9FxCErqMUNiW43yiDpkNoljg1" : {
      "Z6PnyFKSR9MBMd9dfCEs0VMIOog2" : "pending"
    }
  },
  "users" : {
    "YPQYLtXnMbbmFugrJJPYe6rOIJg2" : {
      "email" : "orsrzlqwmt_1488724206@tfbnw.net",
      "name" : "Karen Alaedidibgghi Liangescu",
      "profileURL" : "someURL"
    },
    "Z6PnyFKSR9MBMd9dfCEs0VMIOog2" : {
      "email" : "rbwimniovp_1488724216@tfbnw.net",
      "name" : "Patricia Alaefhcbebjid Warmansen",
      "profileURL" : “someURL”
    },
    "ZyAV7PH4VHWnLyWrWaZty5C9RWT2" : {
      "email" : "bhulxppahm_1488724211@tfbnw.net",
      "name" : "Harry Alaeejdjagjga Greenestein",
      "profileURL" : "someURL"
    },
    "lNI9FxCErqMUNiW43yiDpkNoljg1" : {
      "email" : "axtinlmwes_1488724221@tfbnw.net",
      "name" : "Maria Alaefehgadbdg Valtchanovsky",
      "profileURL" : "someURL"
    }
  }
}

非常感谢任何帮助。干杯!

Answer 1

这是您开始的方式，一旦您有了解析的数据，您就可以使用不同的方法来过滤它，您可以查找 through different stackoverflow questions answered in the past .

let dbRef = FIRDatabase.database().reference.child("friends")
dbRef.observeSingleEvent(of: .value, with: { snapshot in
    if let data = snapshot.value as? [String: [String: String]] {
        for user in data {
            // You'll now have a dictionary with neatly formatted values you can filter
        }
    }
})