问题描述
这个对我没有帮助:Swift 4 parsing json numeric keys with 1+n amount
情况不同。
我有这个 JSON(简化了一点):
{
"1": {
"name": "Tea room","description": "A room for tea"
},"2": {
"name": "Playground","description": "Here you can play all day long"
},"3": {
"name": "Kitchen","description": "Hungry persons can go here"
}
}
我的问题是如何解码。我正在使用 Swift 版本 5。我正在尝试使用 JSONDecoder().decode();
键“1”、“2”和“3”实际上是 ID,由 API 生成。我不知道我会收到多少房间。我不知道他们将拥有什么密钥,但我需要知道密钥(Id)才能走得更远。
我正在做这样的事情:
struct Rooms: Decodable {
let id: Int; //THIS ONE IS MY PROBLEM
let rooms: [Room]?;
}
struct Room: Decodable {
let name: String?;
let description: String?;
private enum CodingKeys: String,CodingKey {
case name,description;
}
}
//Here trying to decode the JSON I got back.
JSONDecoder().decode([Group].self,from: jsonResult);
这让我头疼:)
谁能帮我找到正确的方向?
解决方法
您可以将其解码为字典:[String: Room]
:
JSONDecoder().decode([String: Room].self,from: jsonResult);
,
鉴于此模型(如果属性名称与您的 JSON 键名称相同,则不需要 CodingKeys
):
struct Room: Decodable {
let name: String?
let description: String?
}
您可以将此 JSON 解码为 [String: Room]
类型:
let decoder = JSONDecoder()
do {
let decoded = try decoder.decode([String: Room].self,from: jsonResult)
print(decoded)
} catch {
print(error)
}
,
因为你需要有 id,所以它应该是 Room 的一个属性
struct Room: Decodable {
var id: Int?
let name: String
let description: String
}
这样我们就可以将json解码为[String: Room]的字典,并使用map
为每个房间分配正确的id
do {
let dictionary = try JSONDecoder().decode([String: Room].self,from: data)
let rooms = dictionary.map { tuple -> Room in
var room = tuple.value
room.id = Int(tuple.key)
return room
}
print(rooms)
} catch {
print(error)
}
如果您不想使 id
可选,您可以将其解码为字典字典并在映射时创建 Room 对象
do {
let dictionary = try JSONDecoder().decode([String: [String: String]].self,from: data)
let rooms = dictionary.compactMap { tuple -> Room? in
guard let id = Int(tuple.key),let name = tuple.value["name"],let description = tuple.value["description"] else {
return nil
}
return Room(id: id,name: name,description: description)
}
print(rooms)
} catch {
print(error)
}