Firebase:如何从子节点swift中提取子键值

Question

如何提取孩子的ID值(即followerID1,followerID2 ......)？firebase的结构如下:

Followers:{
    USER_ID:{
        followerID1 = false;
        followerID2 = true;
        followerID3 = true;
    }
}

我在xCode中执行以下操作,但它显示了USER_ID下的整个节点:

self.databaseRef.child("Followers").child(self.USER_ID).Value, withBlock: { (snapshot:FIRDataSnapshot) in
          self.userFollowDump = snapshot
 })

谢谢!我是firebase的新手:)

Answer 1

试试这个:-

• 斯威夫特3

  FIRDatabase.database().reference().child("Followers").child(FIRAuth.auth()!.currentUser!.uid).observeSingleEvent(of: .value, with: { (snapshot) in
          if let userDict = snapshot.value as? [String:AnyObject]{
              for each in userDict{
                  let follwerID = each.0 as! String // Every follwers ID.
              }
          }
      })
  

  如果你正在寻找追随者的价值观true.

      FIRDatabase.database().reference().child("Followers").child(FIRAuth.auth()!.currentUser!.uid).queryOrderedByValue().queryEqual(toValue: true).observeSingleEvent(of: .value, with: {(snap) in
          if let snapDict = snap.value as? [String:AnyObject]{
              for each in snapDict{
  
                  print(each.key)
              }
          }
      })
  

• 斯威夫特2

  FIRDatabase.database().reference().child("Followers").child(FIRAuth.auth()!.currentUser!.uid).observeSingleEventOfType(.Value, withBlock: { (snapshot) in
   if let userDict = snapshot.value as? [String:AnyObject]{
        for each in userDict{
           let follwerID = each.0 as! String // Every follwers ID.
           }
       }
    })
  

  但是如果你正在寻找追随者的价值观true

  FIRDatabase.database().reference().child("Followers").child(FIRAuth.auth()!.currentUser!.uid).queryOrderedByValue().queryEqualToValue(true).observeSingleEventOfType(.Value, withBlock: {(snap) in
       if let snapDict = snap.value as? [String:AnyObject]{
         for each in snapDict{
  
              print(each.key)
          }
      }
  })