arrays - 我将如何分离 JSON 字典值并将它们放入 Swift 数组中？

Question

我正在尝试返回字典字符串值。它返回为:

categories: [yelp1.Zom2(categories: yelp1.Zom3(name: "Delivery")), yelp1.Zom2(categories: yelp1.Zom3(name: "Dine-out"))....]

我如何只返回名称值，例如“Delivery”和“Dine-Out”？//yelp1 只是文件名

示例 JSON 数据

{
    "categories": [
    {
      "categories": {
        "id": 1,
        "name": "Delivery"
      }
    },
    {
      "categories": {
        "id": 2,
        "name": "Dine-out"
      }
    },

这些是我的结构

struct Zom3:Codable{
    let name:String
}
struct Zom2:Codable{

    //let category_id:Int?
    let categories: Zom3

}
struct Zom:Codable{

    //let category_id:Int?
    let categories: [Zom2]

}

我试图解码 Zom3，因为那是名称值所在的位置，但它指出找不到 key 。它不允许我使用 for 循环遍历以至少单独获取字典的每个元素。

override func viewDidLoad() {
    super.viewDidLoad()

    let urlName = "https://developers.zomato.com/api/v2.1/categories"
    let url = URL(string: urlName)
    var urlReq = URLRequest(url: url!)
    urlReq.httpMethod = "GET"
    urlReq.addValue("application/json", forHTTPHeaderField: "Accept")
    urlReq.addValue(zomatoKey, forHTTPHeaderField: "user_key")

    let task = URLSession.shared.dataTask(with: urlReq) { (data, response, error) in
        guard let data = data else {return}

        do {
            let items = try JSONDecoder().decode( Zom.self, from: data)
            print(items)
        }
        catch {
            print(error)
        }
    }
    task.resume()
}

Answer 1

从您所写的内容来看，您的输出似乎来自“print(items)”行。如果这是真的，那么你称为“items”的对象就是顶级结构“Zom”。要获得底层“名称”，我认为您确实需要在“let items = try ...”下使用 for 循环； (而不是“打印(项目)”)

var arrayOfNames: [String] = []
let zoms = item.categories
for item in zoms {
    let possibleName = item.categories?.name
    if let name = possibleName {
         arrayOfNames.append(name)
    }
}
print(arrayOfNames)

如果我没有犯任何错误，这应该创建一个名称数组并打印出“Delivery, Dine-Out”