Question

我有一个我要保存到Firebase的结构。我想在Firebase中添加/创建一个结构列表。我该如何做，并能够检索按分数属性排序的这些项目的n？

struct HighScoreItem {
    var username: String = ""
    var score: Int = 0
    var date: Date = Date()
}

Answer 1

我认为你必须将你的结构包装为属性列表。

首先添加一个函数，用于将结构转换为属性列表，如下所示：

struct HighScoreItem {
  var username: String = ""
  var score: Int = 0
  var date: Date = Date()

  init(from dictionary: [String: Any]) {
    username = dictionary["username"] as! String
    score = dictionary["score"] as! Int
    date = dictionary["date"] as! Date
  }

  func asPropertyList() -> [String: Any] {
    return ["username": username, "score": score, "date", date]
  }

}

稍后您要将其上传到firebase：

let ref = Database.database().reference()
let highScore = HighScoreItem()
ref.child("HighScores").child("0").setValue(highScore.asPropertyList())

并阅读值

ref.child("HighScores").child("0").observeSingleEvent(of: .value, with: { (snapshot) in
  // Get user value
  let value = snapshot.value as? Dictionary
  let highScore = HighScoreItem.init(from: value)
  print(highScore)

  // ...
  }) { (error) in
    print(error.localizedDescription)
}

保存/创建Firebase Swift的结构列表

1 个答案: