Question

我正在从Open - Elevation提取JSON文件，但是无法从提取的数据访问数组的各个段。我当前的视图控制器中包含JSON解析代码，它还允许我自读取整个数组。

struct ElevationArray: Decodable {
    let results: [results]
}

struct results: Decodable {
    let latitude: Double
    let longitude: Double
    let elevation: Double

    init(json: [String: Any]){
      latitude = json["latitude"] as? Double ?? 0.0
      longitude = json["longitude"] as? Double ?? 0.0
      elevation = json["elevation"] as? Double ?? 0.0

    }
}

class FlightInfo: UITableViewController {


    @IBOutlet weak var Lat: UILabel!
    @IBOutlet weak var Long: UILabel!
    @IBOutlet weak var Elevation_label: UILabel!

    var elevationmain: Double?

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        Lat.text = "\(publocation.latitude)"
        Long.text = "\(publocation.longitude)"

        ElevationJSON()


    }


    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func ElevationJSON(){

        let jsonURLString = "https://api.open-elevation.com/api/v1/lookup?locations=41.161758,-8.583933"
        guard let url = URL(string: jsonURLString) else {return}

        URLSession.shared.dataTask(with: url) { (data, response, err) in
            //perhaps check err
            //also perhaps check response status 200 OK

            guard let data = data else { return }


            do {
                //let websiteDescription = try JSONDecoder().decode(WebsiteDescription.self, from: data)
               // print(websiteDescription.name, websiteDescription.description)

               let eleresults = try JSONDecoder().decode(ElevationArray.self, from: data)
               print(eleresults.results)

                let eletest = eleresults.results

                print(eletest)

                //self.elevationmain = Double(eleresults.results)
            } catch let jsonErr {
                print("Error serializing json:", jsonErr)
            }



            }.resume()
    }

}

这是我在打印阵列时运行应用程序时获得的控制台输出。 enter image description here

Answer 1

eleresults.results（或eletest）是results的数组。

要访问所有数据，请使用循环：

for result in eletest {
    print(result.elevation)
}

如果您只想要第一个结果：

if let result = eletest.first {
    print(result.elevation)
}

顺便说一句-您的results结构应重命名为有用的内容，例如Elevation或除results以外的更多描述（请注意，它应以大写字母开头。

Swift JSON解析访问数组

1 个答案: