Question

这是我使用的对象：

以下是我正在使用的JSON数据，我试图访问＆＃34;链接＆＃34;值：

channels =     (
  {
    social =             {
      facebook =                 {
        "facebook_id" = 47360808996;
        link = "https://www.facebook.com/CBS";
      };
      twitter =                 {
        link = "https://twitter.com/CBS";
        "twitter_id" = 97739866;
      }
    }
  }
)

我已经创建了自定义对象来表示JSON字典的每个级别：

class SocialInfo: Mappable {

  var channels: Social?

  required init?(map: Map) {
  }

  func mapping(map: Map) {

    channels <- map["channels"]

  }
}

class Social: Mappable {

  var facebookSocial: Facebook?
  var twitterSocial: Twitter?


  required init?(map: Map) {
  }

  func mapping(map: Map) {

     facebookSocial <- map["facebook"]
     twitterSocial <- map["twitter"]

  }

}


class Facebook: Mappable {

  var facebookLink: NSURL?

  required init?(map: Map) {
  }

  func mapping(map: Map) {

    facebookLink <- (map["link"], URLTransform())

  }
}

最初，我有＆＃34; facebookLink＆＃34;在＆＃34; Facebook＆＃34;作为一个字符串的类，但它保持为零。然后我尝试使用URLTransform将其更改为NSURL类型，但现在却抛出了错误：

如果没有更多的上下文，表达的类型是不明确的

以下是我尝试检索JSON数据的方法：

 func getSocialInfo (completionHandler: @escaping (SocialInfo?, Error?) -> ()){

    Alamofire.request("\(baseURL)/\(apiKey)/show/950", method: .get, encoding: JSONEncoding.default).validate ()
      .responseObject{  (response: DataResponse<SocialInfo>) in

        switch response.result {
        case .success:
          let socialInfo = response.result.value

          print("This is the social info: \(socialInfo?.channels?.facebookSocial?.facebookLink)")


          completionHandler(socialInfo!, nil)

        case .failure(let error):

          print("Sorry there was an error: \(error)")
          completionHandler(nil,error)
          return
        }

  }
}

Answer 1

尝试将链接设置为字符串

var stringURL:String?

获取链接

stringURL <- map["link"]

将stringURL转换为URL

if let url = URL(string: stringURL) {
// do something 
}

另请注意，这不起作用，因为您特别要说facebookDictionary = = Facebook对象。

 class Social: Mappable {

  var facebookSocial: Facebook?
  var twitterSocial: Twitter?

  fileprivate var facebookDictionary:[AnyHashable:Any]? 
  fileprivate var twitterDictionary:[AnyHashable:Any]?
  required init?(map: Map) {
  }

  func mapping(map: Map) {

     facebookDictionary <- map["facebook"]
     twitterDictionary <- map["twitter"]

     if let _facebookDictionary = facebookDictionary,
        let _twitterDictionary = wittertDictionary {

        let twitterMap = Map(mappingType: .fromJSON, JSON: _twitterDictionary)
        let facebookMap = Map(mappingType: .fromJSON, JSON: _facebookDictionary)

     /// Here you can initiate both object using map.

        facebookSocial = Facebook(map: facebookMap)
        twitterSocial = Twitter(map: twitterMap)

    /// If you want to use mapping function, set this as:

        facebookSocial = Facebook()
        twitterSocial.mapping(map: twitterMap)

        facebookSocial = Facebook()
        twitterSocial.mapping(map: twitterMap)
     }

  }

}

由于您没有使用社交字典创建新地图，因此两个对象始终为nil

社交相同，首先从社交map创建dictionary。

如何使用AlamoFire / ObjectMapper访问嵌入在JSON字典中的链接？

1 个答案: