所以我一直在使用 Swift 4 的新 Decodable 协议(protocol)并且它很棒，但现在我遇到了一个我找不到答案的实例。我正在尝试使用 decodable 来解析 Reddit Comments API 响应。这是一个简单的例子。 (请注意，这不是完整的响应，只是一些快速的示例)

这是我的问题的一个简单示例。如果您查看“children”中的“data”键，则字典包含不同的数据。有没有办法在 children 数组中有两个不同的 JSON 对象，这取决于它们具有什么内容或基于它们在数组中的位置？

[{
    "kind": "Listing",
    "data": {
        "modhash": "kskppiefdzafc020177a3995ccd7f13b4ba0a8ca70e691a510",
        "whitelist_status": "all_ads",
        "children": [{
            "kind": "t3",
            "data": {
                "domain": "i.redd.it",
                "approved_at_utc": null,
                "mod_reason_by": null,
                "selftext_html": "Hello world!!!"
            }
        }]
    }
}, {
    "kind": "Listing",
    "data": {
        "modhash": "kskppiefdzafc020177a3995ccd7f13b4ba0a8ca70e691a510",
        "whitelist_status": "all_ads",
        "children": [{
            "kind": "t3",
            "data": {
                "domain": "i.redd.it",
                "approved_at_utc": null,
                "author": null,
                "body": "Hello world"
            }
        }]
    }

}]

基本上我很好奇的可能是这个....

public struct CommentRoot: Decodable {
    struct Datafield: Decodable {
        let modhash: String
        let whitelist_status: String
        let children: [Comment]? // <------ Can be 1 of 2 types of comment that vary.
        let after: String?
        let before: String?
    }
    let data: Datafield
    let kind: String
}

最佳答案

希望对你有帮助

import Foundation

struct Children : Decodable {

    let data : DataInfo?
    let kind : String?


    enum CodingKeys: String, CodingKey {
        case data
        case kind = "kind"
    }
    init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        data = try DataInfo(from: decoder)
        kind = try values.decodeIfPresent(String.self, forKey: .kind)
    }


}

       struct DataInfo : Decodable {

        let approvedAtUtc : String?
        let author : String?
        let body : String?
        let domain : String?
        let children : [Children]?
        let modhash : String?
        let whitelistStatus : String?


        enum CodingKeys: String, CodingKey {
            case approvedAtUtc = "approved_at_utc"
            case author = "author"
            case body = "body"
            case domain = "domain"
            case children = "children"
            case modhash = "modhash"
            case whitelistStatus = "whitelist_status"
        }
        init(from decoder: Decoder) throws {
            let values = try decoder.container(keyedBy: CodingKeys.self)
            approvedAtUtc = try values.decodeIfPresent(String.self, forKey: .approvedAtUtc)
            author = try values.decodeIfPresent(String.self, forKey: .author)
            body = try values.decodeIfPresent(String.self, forKey: .body)
            domain = try values.decodeIfPresent(String.self, forKey: .domain)
            children = try values.decodeIfPresent([Children].self, forKey: .children)
            modhash = try values.decodeIfPresent(String.self, forKey: .modhash)
            whitelistStatus = try values.decodeIfPresent(String.self, forKey: .whitelistStatus)
        }


    }

关于ios - 当 JSON 以具有不同属性的多个数组为根时如何使用 Swift 4 Codable，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/47825646/