将 JSON 字符串映射到自定义枚举情况而无需访问 Swift 中的枚举实现的最佳方法？

Question

考虑以下简单的 JSON：

{
  "title": "Some title",
  "subtitle": "Some subtitle",
  "button_type": "rounded"
}

这是我当前解码 ButtonType 字段的方法：

// I dont have access to this enums implementation as it comes from a 3rd party lib.
enum ButtonType {
    case squared
    case simple
    case rounded
    case normal
}

struct ResponseModel: Decodable {
    var title: String
    var subtitle: String
    var type: ButtonType
    
    enum CodingKeys: String, CodingKey {
        case title = "title"
        case subtitle = "subtitle"
        case type = "button_type"
    }
    
    init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        title = try container.decode(String.self, forKey: .title)
        subtitle = try container.decode(String.self, forKey: .subtitle)
        let stringType = try container.decode(String.self, forKey: .type)
        switch stringType {
        case "squared":
            type = .squared
        case "simple":
            type = .simple
        case "rounded":
            type = .rounded
        default:
            type = .normal
        }
    }
}

有没有更漂亮的方法来完成将字符串解码为自定义枚举，而无需在纯字符串上迭代令人讨厌的 switch 语句？遗憾的是，我无法访问枚举实现，因为它来自第三方库。如果我这样做，我会让枚举符合 String 和 Codable 并让 Codable 发挥其魔力，但我不这么做。

谢谢！

Answer 1

您可以创建自己的

enum

enum MyButtonType: String {
    case squared
    case simple
    case rounded
    case normal

    var toButtonType: ButtonType {
         switch self {
              case .squared: return .squared
              case .simple: return .simple
              case .rounded: return .rounded
              case .normal: return .normal
         }
    }
}