如何解码swift中有动态键值的json？

struct DynamicJSON: Codable {
    private var dynamicValues: [String: Any]

    init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: DynamicCodingKeys.self)
        dynamicValues = [String: Any]()

        for key in container.allKeys {
            if let value = try? container.decode(Bool.self, forKey: key) {
                dynamicValues[key.stringValue] = value
            } else if let value = try? container.decode(Int.self, forKey: key) {
                dynamicValues[key.stringValue] = value
            } else if let value = try? container.decode(Double.self, forKey: key) {
                dynamicValues[key.stringValue] = value
            } else if let value = try? container.decode(String.self, forKey: key) {
                dynamicValues[key.stringValue] = value
            }
        }
    }

    func value<T>(forKey key: String) -> T? {
        return dynamicValues[key] as? T
    }

    private struct DynamicCodingKeys: CodingKey {
        var stringValue: String
        init?(stringValue: String) {
            self.stringValue = stringValue
        }

        var intValue: Int? { return nil }
        init?(intValue: Int) { return nil }
    }
}

{
    "name": "John",
    "age": 25,
    "isStudent": true
}

let json = """
{
    "name": "John",
    "age": 25,
    "isStudent": true
}
"""

let jsonData = json.data(using: .utf8)!
let decoder = JSONDecoder()

do {
    let dynamicJSON = try decoder.decode(DynamicJSON.self, from: jsonData)

    let name: String? = dynamicJSON.value(forKey: "name")
    let age: Int? = dynamicJSON.value(forKey: "age")
    let isStudent: Bool? = dynamicJSON.value(forKey: "isStudent")

    print(name)        // 输出: Optional("John")
    print(age)         // 输出: Optional(25)
    print(isStudent)   // 输出: Optional(true)
} catch {
    print("解码失败: \(error)")
}