Swift根据响应类型为JSON字段值动态选择可编码结构

struct Response<T: Codable>: Codable {
    let data: T
    let status: Int
    let message: String
}

struct User: Codable {
    let name: String
    let age: Int
}

func decodeResponse<T: Codable>(data: Data, responseType: T.Type) throws -> Response<T> {
    let decoder = JSONDecoder()
    let response = try decoder.decode(Response<T>.self, from: data)
    return response
}

// 示例用法
let jsonData = """
{
    "data": {
        "name": "John",
        "age": 25
    },
    "status": 200,
    "message": "Success"
}
""".data(using: .utf8)!

do {
    let response = try decodeResponse(data: jsonData, responseType: User.self)
    print(response.data.name) // 输出: John
    print(response.data.age) // 输出: 25
} catch {
    print("解码失败: \(error)")
}