如何使用 Codable 处理这种 JSON 格式答案

【问题标题】：How can I deal with this kind of JSON formate with Codable如何使用 Codable 处理这种 JSON 格式
【发布时间】：2020-04-07 06:34:35
【问题描述】：

有时“box”数组包含有时为空的字典（“box”：[]）。我尝试了很多次，但每次都失败并显示此错误。

错误::无法读取数据，因为它的格式不正确。

    {
                "id": 57,
                "title": "PRIVATE SET  :: Royal Blue Colour",
                "description": "3 of your selected Fragrances from our Classic Line in an overwhelmingly unique Royal Blue wooden box.",
                "volume": "",
                "price": 0,
                "sub-category": "Assemblage",
                "image": "http://192.168.1.163/ramasaat/public/storage/images/Products/e0dc5e9d15704ccac5c0965e9e2c782e.jpg",
                "related": [
                    {
                        "id": 55,
                        "title": "ELITE SET  :: Royal Blue Colour",
                        "description": "8 of your selected Fragrances from our Classic Line in an overwhelmingly unique Royal Blue wooden box.",
                        "volume": "",
                        "price": 0,
                        "category": "Assemblage",
                        "sub-category": "Assemblage",
                        "image": "http://192.168.1.163/ramasaat/public/storage/images/Products/deb955bd41baac2e98ee026c28734fb1.jpg"
                    },
                .
                .
                    .
                ],
                "num_item": 3,
===============>        "box": [
                    {
                        "id": 1,
                        "title": "MAYYAS",
                        "description": "An unmistakable presence and a charming aura of musk with an oriental flair. This fragrance merges a mixture of contrasting scents flawlessly and is full of mystery and charisma.",
                        "price": 990,
                        "image": "http://192.168.1.163/ramasaat/public/storage/images/Products/07c44b5a8fea99804ac57520103f755e.jpg"
                    },
                    .
                .
                .
                .

                ]
            }

【问题讨论】：

显示你使用的结构。
打印error 实例而不是error.localizedDescription。它会准确地告诉你哪里出了问题。
可以为您做与“相关”相同的事情
@vadian 很棒的人.....我用你的回答解决了这个问题

标签： swift codable

【解决方案1】：

这样使用

struct RootClass : Codable {

    let box : [Box]?
    let descriptionField : String?
    let id : Int?
    let image : String?
    let numItem : Int?
    let price : Int?
    let related : [Related]?
    let subcategory : String?
    let title : String?
    let volume : String?


    enum CodingKeys: String, CodingKey {
        case box = "box"
        case descriptionField = "description"
        case id = "id"
        case image = "image"
        case numItem = "num_item"
        case price = "price"
        case related = "related"
        case subcategory = "sub-category"
        case title = "title"
        case volume = "volume"
    }
    init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        box = try values.decodeIfPresent([Box].self, forKey: .box)
        descriptionField = try values.decodeIfPresent(String.self, forKey: .descriptionField)
        id = try values.decodeIfPresent(Int.self, forKey: .id)
        image = try values.decodeIfPresent(String.self, forKey: .image)
        numItem = try values.decodeIfPresent(Int.self, forKey: .numItem)
        price = try values.decodeIfPresent(Int.self, forKey: .price)
        related = try values.decodeIfPresent([Related].self, forKey: .related)
        subcategory = try values.decodeIfPresent(String.self, forKey: .subcategory)
        title = try values.decodeIfPresent(String.self, forKey: .title)
        volume = try values.decodeIfPresent(String.self, forKey: .volume)
    }


}


    struct Related : Codable {

        let category : String?
        let descriptionField : String?
        let id : Int?
        let image : String?
        let price : Int?
        let subcategory : String?
        let title : String?
        let volume : String?


        enum CodingKeys: String, CodingKey {
            case category = "category"
            case descriptionField = "description"
            case id = "id"
            case image = "image"
            case price = "price"
            case subcategory = "sub-category"
            case title = "title"
            case volume = "volume"
        }
        init(from decoder: Decoder) throws {
            let values = try decoder.container(keyedBy: CodingKeys.self)
            category = try values.decodeIfPresent(String.self, forKey: .category)
            descriptionField = try values.decodeIfPresent(String.self, forKey: .descriptionField)
            id = try values.decodeIfPresent(Int.self, forKey: .id)
            image = try values.decodeIfPresent(String.self, forKey: .image)
            price = try values.decodeIfPresent(Int.self, forKey: .price)
            subcategory = try values.decodeIfPresent(String.self, forKey: .subcategory)
            title = try values.decodeIfPresent(String.self, forKey: .title)
            volume = try values.decodeIfPresent(String.self, forKey: .volume)
        }


    }

    struct Box : Codable {

        let descriptionField : String?
        let id : Int?
        let image : String?
        let price : Int?
        let title : String?


        enum CodingKeys: String, CodingKey {
            case descriptionField = "description"
            case id = "id"
            case image = "image"
            case price = "price"
            case title = "title"
        }
        init(from decoder: Decoder) throws {
            let values = try decoder.container(keyedBy: CodingKeys.self)
            descriptionField = try values.decodeIfPresent(String.self, forKey: .descriptionField)
            id = try values.decodeIfPresent(Int.self, forKey: .id)
            image = try values.decodeIfPresent(String.self, forKey: .image)
            price = try values.decodeIfPresent(Int.self, forKey: .price)
            title = try values.decodeIfPresent(String.self, forKey: .title)
        }


    }

【讨论】：