Question

我有一些我正在从Wunderground下载的天气数据，当我访问网站时，信息会正确地返回，但是当我解析此信息时，我所拥有的标签应该更改。这是代码......

let jsonResult: AnyObject! = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary

                if let city = jsonResult["current_observation"] as? NSDictionary {
                    if let weatherInfo = city["estimated"] as? NSDictionary{
                        if let  currentTemp = weatherInfo["feelslike_string"] as? NSString {


                            self.temperatureLabel.text = currentTemp
                        }
                    }
                }

这是JSON（部分内容）：

{
    "current_observation" =     {
        UV = 0;
        "dewpoint_c" = 16;
        "dewpoint_f" = 60;
        "dewpoint_string" = "60 F (16 C)";
        "display_location" =         {
            city = "San Francisco";
            country = US;
            "country_iso3166" = US;
            elevation = "47.00000000";
            full = "San Francisco, CA";
            latitude = "37.77500916";
            longitude = "-122.41825867";
            magic = 1;
            state = CA;
            "state_name" = California;
            wmo = 99999;
            zip = 94101;
        };
        estimated =         {
        };
        "feelslike_c" = "16.4";
        "feelslike_f" = "61.5";
        "feelslike_string" = "61.5 F (16.4 C)";
        "forecast_url" = "http://www.wunderground.com/US/CA/San_Francisco.html";
        "heat_index_c" = NA;
        "heat_index_f" = NA;
        "heat_index_string" = NA;
        "history_url" = "http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=KCASANFR49";
        icon = cloudy;

任何帮助将不胜感激！谢谢

Answer 1

您的JSON看起来格格不入。 estimated将是一个空字典，所以这一行：

if let currentTemp = weatherInfo["feelslike_string"] as? NSString

不会返回true，因为weatherInfo没有密钥"feelslike_string"的对象 - 它会返回nil。

"feelslike_string"是"current_observation"字典的成员，而不是"estimated"字典的成员。此JSON中的"estimated"字典为空，并且没有键"feelslike_string"的值。

所以我们需要将代码更改为：

if let currentObs = jsonResult["current_observation"] as? NSDictionary {
    if let currentTemp = currentObs["feelslike_string"] as? NSString {
        self.temperatureLabel.text = currentTemp
    }
}

试图解析JSON数据，但标签没有在Swift中更新

1 个答案: