无法分配“[Currency]”类型的值？输入“[Currency]?.Type”

Question

我正在尝试解码具有可选数组的结构

struct AppInitData:Decodable{

    var ApplicationID:String?
    var Currencies = [Currency]?

    enum CodingKeys: String, CodingKey {
        case ApplicationID = "ApplicationID"
        case Currencies = "Currencies"
    }

    enum DataKeys: String, CodingKey {
        case AppInitData = "Data"
    }

    public init(from decoder: Decoder) throws {

        let values = try decoder.container(keyedBy: DataKeys.self)
        let productValues = try values.nestedContainer(keyedBy: CodingKeys.self, forKey: .AppInitData)

        self.Currencies = try productValues.decodeIfPresent([Currency].self,forKey:.Currencies)

    }

编译错误 1:

var Currencies = [Currency]? ==> Expected member name or constructor call after type name

编译错误2：

self.Currencies = try productValues.decodeIfPresent([Currency].self,forKey:.Currencies) ==> Cannot assign value of type '[Currency]?' to type '[Currency]?.Type'

不确定这里缺少什么，有人可以指出吗？

Answer 1

这样声明

   var Currencies :[Currency]?

无法分配“[Currency]”类型的值？输入“[Currency]?.Type”

Cannot assign value of type '[Currency]?' to type '[Currency]?.Type'

json

swift4

decodable