arrays - 如何在json数组结构中添加附加字段

Question

我需要添加额外的 bool 字段来制作可选择的品牌和型号表。原始 json 结构是:

    {
        "brands": [
            {
                "id": "19",
                "name": "Audi",
                "sort": "1",
                "num": 1,
                "models": [
                    {
                        "id": "190",
                        "name": "TTS",
                        "num": 1
                    },
                    {
                        "id": "189",
                        "name": "TT",
                        "num": 2
                    },
                    {
                        "id": "188",
                        "name": "V8",
                        "num": 3
                    },
                    {
                        "id": "187",
                        "name": "SQ5",
                        "num": 4
                    }
                ],
......

我需要在品牌和型号结构中添加 isExpished: Bool = false。所以数组应该是这样的:

{
        "brands": [
            {
          --->  "isExpanded": false,
                "id": "19",
                "name": "Audi",
                "sort": "1",
                "num": 1,
                "models": [
                    {
                 --->   "isExpanded": false,
                        "id": "190",
                        "name": "TTS",
                        "num": 1
                    },

我的模型:

struct auto_data: Decodable {
    var brands: [brands]
    var gearbox: [gearbox]
    var fuel: [fuel]
    var version: String
}

struct brands: Decodable {
    var id: String
    var name: String
    var sort: String
    var num: Int
    var models: [brand_models]
}

struct brand_models: Decodable {
    var id: String
    var name: String
    var num: Int
}

获取 json 我使用:

func get_data (order_type: String, localization: String, version: String, completion: @escaping ([brands]?) -> Void) {
    let encodedBodyParams = "order_type=\(order_type)&localization=\(localization)&version=\(version)"
    let url = URL(string: "http://skat.az/forapi/api/get_data.php")
    Alamofire.request(url!, method: .post, parameters: [:], encoding: encodedBodyParams, headers: [:]).responseJSON { (response) in
        if response.result.isSuccess {
            do {
                let result = response.data
                let data = try JSONDecoder().decode(auto_data.self, from: result!)

                completion(data.brands)
            } catch {
                print("Error: \(error)")
            }
            print("models ОК!")
        } else {
            print("error response: \(String(describing: response.error))")
            completion(nil, nil, nil)
        }
    }
}

我不想遍历数组的所有元素并将它们放入另一个具有正确结构的元素中。还有其他方法可以改变数组的结构吗？

Answer 1

首先请遵守结构体和类名以大写字母开头且驼峰命名的命名约定。单数形式的进一步名称结构。就语言语义而言，您正在创建一个 BrandModel，而不是一个 BrandModels

如果您需要在符合 Decodable 的结构中添加自定义成员，则必须指定 CodingKeys

在大多数情况下，将解码后的结构成员声明为常量就足够了 (let)

struct Brand: Decodable {

    private enum CodingKeys : String, CodingKey {
        case id, name, sort, num, models
    }

    var isExpanded = false
    let id: String
    let name: String
    let sort: String
    let num: Int
    let models: [BrandModel]
}

struct BrandModel: Decodable {

    private enum CodingKeys : String, CodingKey {
        case id, name, num
    }

    var isExpanded = false
    let id: String
    let name: String
    let num: Int
}