从 firebase swift 获取数据

Question

我正在尝试从我的 firebase 数据库中接收所有用户的全名，我目前正在做这样的事情：

ref.observeSingleEvent(of: .value, with: { (snapshot) in
  if let dictionary = snapshot.value as? [String: AnyObject] {
    let friend = FriendsModel()
  
    friend.fullname = dictionary["fullname"] as! String?
    friend.email = dictionary["email"] as! String?
    friend.birthDate = dictionary["Birth date"] as! String?
                
    friend.provider = dictionary["provider"] as! String?
                
    print(friend.fullname)
  }
})

但是 postDict["fullname"] 返回 nil。

firebase 数据库的图片： Firebase Database

func fetchUsers () {
  ref.observeSingleEvent(of:.value, with: { snapshots in
  if  snapshots.exists() {
     guard let snapshot = snapshots.children.allObjects as?    [FIRDataSnapshot] else { return }
      for eachSnap in snapshot {
        guard let eachUserDict = snapshots.value as? Dictionary<String,AnyObject> else { return }
        // eachUserDict is an object/ dictionary representation for each user
        //this prints all the information of the users
        print (eachUserDict)
        let fullName = eachUserDict["fullname"] as? String
        //this returns nil :(
        print(fullName)
      }
    }
  })
}

这是我收到的图片： enter image description here

Answer 1

我认为你没有告诉ref 在哪里观察。改变这一行

  ref.observeSingleEvent(of: .value, with: { (snapshot) in

到

    guard let id = FIRAuth.auth()?.currentUser?.uid else {return}
    ref.child("users").child(id).observeSingleEvent(of: .value) {  (snapshots) in

更新： 如果您想获取所有用户的全名，请尝试以下操作：

ref.child("users").observeSingleEvent(of:.value) { snapshots in 
        if  snapshots.exists() {
            guard let snapshot = snapshots.children.allObjects as? [FIRDataSnapshot] else { return }
     for eachSnap in snapshot {
         guard let eachUserDict = snap.value as? Dictionary<String,AnyObject> else { return }
      // eachUserDict is an object/ dictionary representation for each user
              let fullName = eachUserDict["fullName"] as? String 
    }
}