快速检索数据 Firebase

Question

我正在尝试检索已保存在对象中的字符串 key

  func retrieveData() {
    let refAll = Database.database().reference().child("Playground")
    refAll.observe(.value) { (snapshot) in
        if let snapshotValue = snapshot.value as? [String:Any] {
            var playgroundSnapshot = snapshotValue
            let playgroundKeys = Array(playgroundSnapshot.keys)
            self.playgroundArray.removeAll()
            for key in playgroundKeys  {
                guard
                    let value = playgroundSnapshot[key] as? [String : Any]
                    else {
                        continue
                }
                let title = value["title"] as! String
                let city = value["city"] as! String
                let location = value["location"] as! String
                let price = value["price"] as! String

                let playground = Playground(title: title, price: price, location: location, city: city, availblePlayground: true)
                self.playgroundArray.append(playground)
            }
            self.tabeView.reloadData()
        }
    }
}

在 PlaygroundArray 中，每个对象都有一个键

 keySelected = playgroundArray[indexPath.row].key

但我不知道为什么 keySelected 是 nil 即使 PlaygroundArray 有对象

Answer 1

playgroundArray 不包含“key”。您必须设置Playground Struct。添加var key:String?并将其添加到init()函数中。

let playground = Playground(title: title, price: price, location: location, city: city, availblePlayground: true)

到

let playground = Playground(title: title, price: price, location: location, city: city, availblePlayground: true, key: key)


self.playgroundArray.append(playground)