Swift - 如何使这个结构符合 Codable？

Question

我有这个结构

struct Photo: Codable {
    var image: UIImage
    let caption: String?
    let location: CLLocationCoordinate2D?
}

private enum CodingKeys: String, CodingKey {
    case image = "image"
    case caption = "caption"
    case location = "location"
}

我得到这 2 个错误：

Type 'Photo' does not conform to protocol 'Decodable'

Type 'Photo' does not conform to protocol 'Encodable'

Answer 1

'Photo' 不符合协议 Encodable/Decodable 因为 UIImage 不能符合 Codable。另外 CLLocationCoordinate2D 不能符合 Codable。 您可以使用 Data 类型指定 var image，然后从 Data.

获取 UIImage

像这样：

struct Photo: Codable {
    var imageData: Data
    let caption: String?
    let location: String?

    func getImage(from data: Data) -> UIImage? {
        return UIImage(data: data)
    }
}

private enum CodingKeys: String, CodingKey {
    case imageData = "image"
    case caption = "caption"
    case location = "location"
}