尝试使用 JSON 数组插入非属性列表对象

Question

基本上，我已经正确解析了我的数据。但是，当我尝试访问数据时。它声称我正在尝试将非属性列表对象插入到 UserDefaults 数组中。我如何能够以某种方式将其转换为属性列表对象？或者我如何能够将 JSON 数组存储为字符串？

var status = UserDefaults.standard.array(forKey: "status") ?? []
struct Response: Codable {
        let weather: [MyResult]
    }
    struct MyResult: Codable {
        let main: String
    }
func getData(from url:String) {
        
        URLSession.shared.dataTask(with: URL(string:url)!, completionHandler: {
            data, response, error in
            guard let data = data, error == nil else {
                print("Something went wrong")
                return
            }
            // have data
            var result: Response?
            do {
                result = try JSONDecoder().decode(Response.self, from: data)
            } catch {
                print(error.localizedDescription)
            }
            guard let json = result else {
                return
            }
            print(type(of: json.weather)) // Array
            
            UserDefaults.standard.set(json.weather, forKey: "status") // Here is the error
            print(status)
            }).resume()
    }

编辑：当我打印状态时，什么都没有。

func getData(from url:String) {
        
        URLSession.shared.dataTask(with: URL(string:url)!, completionHandler: {
            data, response, error in
            guard let data = data, error == nil else {
                print("Something went wrong")
                return
            }
            // have data
            var result: Response?
            do {
                result = try JSONDecoder().decode(Response.self, from: data)
            } catch {
                print(error.localizedDescription)
            }
            guard let json = result else {
                return
            }
            print(type(of: json.weather)) // Array
            do {
                 // Store it with
                let data = try JSONEncoder().encode(json.weather)
                UserDefaults.standard.set(data, forKey: "status")
                

                //  Read it
                if let data = UserDefaults.standard.data(forKey:"status") {
                  let res = try JSONDecoder().decode([MyResult].self,from:data)
                }
            }
            catch {
               print(error)
            }
            print(status)
            }).resume()
    }

Answer 1

你需要

do {
     // Store it with  
    let data = try JSONEncoder().encode(json.weather)
    UserDefaults.standard.set(data, forKey: "status")

    //  Read it 
    if let data = UserDefaults.standard.data(forKey:"status") {
      let res = try JSONDecoder().decode([MyResult].self,from:data)
    }  
}
catch {
   print(error)
}

Answer 2

保持变量的命名唯一，以免混淆或混淆。这是为您整理的代码。

func getData(from url: String) {
    URLSession.shared.dataTask(with: URL(string: url)!) { data, _, error in
        guard let data = data else {
            if let error = error { print(error) }
            return
        }
        do {
            let response = try JSONDecoder().decode(Response.self, from: data)
            print("got response: \(response)")
            let dataToStore = try JSONEncoder().encode(response.weather)
            UserDefaults.standard.set(dataToStore, forKey: "status") // set data to userdefaults
            guard let dataRetrieved = UserDefaults.standard.data(forKey: "status") else { return } // retrieve back weather
            let weather = try JSONDecoder().decode([MyResult].self, from: dataRetrieved)
            print("got weather from user defaults: \(weather)")
        } catch {
            print(error.localizedDescription)
        }
    }.resume()
}