问题访问" dailysummary" Wunderground API部分

时间:2015-08-13 22:21:29

标签: swift wunderground

我有一组函数可以从Wunderground API中检索数据。但是,因为" dailysummary"部分以某种方式包含在数组中,我无法弄清楚如何访问它。这是我无法访问的部分:

"history": {
    "dailysummary": [
     { "date": {
     "pretty": "12:00 PM PDT on August 12, 2015",
    "year": "2015",
    "mon": "08",
    "mday": "12",
    "hour": "12",
    "min": "00",
    "tzname": "America/Los_Angeles"
    },
    "fog":"0","rain":"0","snow":"0","snowfallm":"0.00","snowfalli":"0.00","monthtodatesnowfallm":"", "monthtodatesnowfalli":"","since1julsnowfallm":"", "since1julsnowfalli":"","snowdepthm":"", "snowdepthi":"","hail":"0","thunder":"0","tornado":"0","meantempm":"26", "meantempi":"79","meandewptm":"16", "meandewpti":"60","meanpressurem":"1014", "meanpressurei":"29.94","meanwindspdm":"9", "meanwindspdi":"5","meanwdire":"","meanwdird":"331","meanvism":"16", "meanvisi":"10","humidity":"","maxtempm":"33", "maxtempi":"91","mintempm":"19", "mintempi":"66","maxhumidity":"78","minhumidity":"34","maxdewptm":"17", "maxdewpti":"62","mindewptm":"15", "mindewpti":"59","maxpressurem":"1016", "maxpressurei":"30.01","minpressurem":"1012", "minpressurei":"29.88","maxwspdm":"24", "maxwspdi":"15","minwspdm":"0", "minwspdi":"0","maxvism":"16", "maxvisi":"10","minvism":"16", "minvisi":"10","gdegreedays":"28","heatingdegreedays":"0","coolingdegreedays":"14","precipm":"0.00", "precipi":"0.00","precipsource":"","heatingdegreedaysnormal":"0","monthtodateheatingdegreedays":"0","monthtodateheatingdegreedaysnormal":"0","since1sepheatingdegreedays":"","since1sepheatingdegreedaysnormal":"","since1julheatingdegreedays":"0","since1julheatingdegreedaysnormal":"17","coolingdegreedaysnormal":"5","monthtodatecoolingdegreedays":"106","monthtodatecoolingdegreedaysnormal":"69","since1sepcoolingdegreedays":"","since1sepcoolingdegreedaysnormal":"","since1jancoolingdegreedays":"600","since1jancoolingdegreedaysnormal":"280" }
    ]
}

有关我如何调用API的信息,请参阅此网站:http://devdactic.com/rest-api-parse-json-swift/

1 个答案:

答案 0 :(得分:1)

您可能正在使用SwiftyJSON或其他库,但对于我的示例,我只是使用NSJSONSerialization。

在这里,我进入“历史”字典,然后进入“dailysummary”字典,我将结果转换为字典数组(假设您的JSON字典也被命名为“json”):

if let json = NSJSONSerialization.JSONObjectWithData(data, options: nil, error: &err) as? [String:AnyObject] {
    if let history = json["history"] as? [String:AnyObject],
        let daily = history["dailysummary"] as? [[NSObject:AnyObject]] {
        // "daily" is our array
    }
}

然后我在数组中循环(在你的例子中,里面只有一个对象,但可能有很多):一些值是字符串,其他是字典,比如“date”。

我正在使用“if let”来安全地展开并投射内容:

if let json = NSJSONSerialization.JSONObjectWithData(data, options: nil, error: &err) as? [String:AnyObject] {
    if let history = json["history"] as? [String:AnyObject],
        let daily = history["dailysummary"] as? [[NSObject:AnyObject]] {
        for item in daily {
            for (key, _) in item {
                println(key) // "mintempm", "mindewpti", "since1sepheatingdegreedaysnormal", "meantempm", etc
            }
            if let coolingdegreedaysnormal = item["coolingdegreedaysnormal"] as? String {
                println(coolingdegreedaysnormal) // "5"
            }
            if let date = item["date"] as? [String:AnyObject], let pretty = date["pretty"] as? String  {
                println(pretty) // "12:00 PM PDT on August 12, 2015"
            }
        }
    }
}

如果您使用的是SwiftyJSON或同等产品,则不必手动执行强制转换,但您必须使用特定于库的语法,可能是这种风格的东西:

for item in json["history"]["dailysummary"].array {
    // ...
}