使用類繼承是否會破壞類的可解碼性。例如下面的代碼class Server : Codable {    var id : Int?}class Development : Server {    var name : String?    var userId : Int?}var json = "{\"id\" : 1,\"name\" : \"Large Building Development\"}"let jsonDecoder = JSONDecoder()let item = try jsonDecoder.decode(Development.self, from:json.data(using: .utf8)!) as Developmentprint(item.id ?? "id is nil")print(item.name ?? "name is nil") here輸出為：1name is nil現在，如果我將其反轉，則名稱會解碼，而id不會。class Server {    var id : Int?}class Development : Server, Codable {    var name : String?    var userId : Int?}var json = "{\"id\" : 1,\"name\" : \"Large Building Development\"}"let jsonDecoder = JSONDecoder()let item = try jsonDecoder.decode(Development.self, from:json.data(using: .utf8)!) as Developmentprint(item.id ?? "id is nil")print(item.name ?? "name is nil")輸出為：id is nilLarge Building Development而且您不能在兩個類中都表示Codable。