已获取 json 文件，因为 NSArray 仅包含第一个字符

Question

我有一个 json file 看起来像这样：


[
  {
    "tn_newsid": 144377,
    "tn_midashi": "知床半島とオホーツク海の絶景が広がる",
    "tn_name": "北海道立オホーツク公園オートキャンプ場てんとらんど",
    "tn_ktel": "0152-45-27",
    "tn_url": "",
    "tn_kdo": 144.239526856306,
    "tn_ido": 43.9880220633556,
    "tn_im1name": "144377_1.jpg",
    "tn_im2name": "144377_2.jpg",
    "tn_im3name": "144377_3.jpg",
    "tn_im4name": "144377_4.jpg",
    "type": 0,
    "nico_recommended": 0
  },
  {
// etc ....

直到现在我都是通过截取这段代码获取数据


seasonInfoService.seasonServerDataJson(jsoncompleted: { () in
let responseData: Data =  self.seasonInfoService.UpdateJsonString.data(using: String.Encoding.utf8)!
    do{
        let items = try JSONSerialization.jsonObject(with: responseData) as! Dictionary<String,Any>

但是 json file 以 [ 开头，所以我需要将 Dictionary<String,Any> 更改为 NSArray

因为我收到这个错误代码


Could not cast value of type '__NSArrayI' (0x7fff86cd0128) to 'NSDictionary'

我的代码现在看起来像


facilitiesService.facilitiesServerDataJson(urlToFetch: url_, jsoncompleted: { () in
let responseData: Data =  self.facilitiesService.UpdateJsonString.data(using: String.Encoding.utf8)!
    do{
        let items = try JSONSerialization.jsonObject(with: responseData) as! NSArray
        print(items)

但是打印语句只显示 [ ，请问如何将其更改为正确的词典列表？

Answer 1

首先创建一个符合Decodable的结构体。 good/necessary映射JSON数据

struct MyStruct: Decodable {
    let tn_newsid: Int
    let tn_midashi: String
    let tn_name: String
    let tn_ktel: String
    let tn_url: String
    let tn_kdo: Double
    let tn_ido: Double
    let tn_im1name: String
    let tn_im2name: String
    let tn_im3name: String
    let tn_im4name: String
    let type: Int
    let nico_recommended: Int

}

那么假设您的 JSON 回复如下所示：

let responseData: String = """
        [
        {
          "tn_newsid": 1477,
          "tn_midashi": "知床半島とオホーツク海の絶景が広がる",
          "tn_name": "北海道立オホーツク公園オートキャンプ場てんとらんど",
          "tn_ktel": "0152-45-27",
          "tn_url": "",
          "tn_kdo": 144.239526856306,
          "tn_ido": 43.9880220633556,
          "tn_im1name": "144377_1.jpg",
          "tn_im2name": "144377_2.jpg",
          "tn_im3name": "144377_3.jpg",
          "tn_im4name": "144377_4.jpg",
          "type": 0,
          "nico_recommended": 2
        },
        {
          "tn_newsid": 144377,
          "tn_midashi": "知ホーツク海の絶景が広がる",
          "tn_name": "北海道立オホートキャンプ場てんとらんど",
          "tn_ktel": "0152-45-27",
          "tn_url": "",
          "tn_kdo": 144.239526856306,
          "tn_ido": 46.9880220633556,
          "tn_im1name": "144377_1.jpg",
          "tn_im2name": "144377_2.jpg",
          "tn_im3name": "144377_3.jpg",
          "tn_im4name": "144377_4.jpg",
          "type": 0,
          "nico_recommended": 0
        }
            ]
            """

现在像这样解析响应：

let jsonData = responseData.data(using: .utf8)!
let decodedItems: [MyStruct] = try! JSONDecoder().decode([MyStruct].self, from: jsonData)
decodedItems.forEach({print(">>> \([=12=])")})

实际上，您最好避免使用 force-unwrapping 数据和解码项。

输出：

>>> MyStruct(tn_newsid: 1477, tn_midashi: "知床半島とオホーツク海の絶景が広がる", tn_name: "北海道立オホーツク公園オートキャンプ場てんとらんど", tn_ktel: "0152-45-27", tn_url: "", tn_kdo: 144.239526856306, tn_ido: 43.9880220633556, tn_im1name: "144377_1.jpg", tn_im2name: "144377_2.jpg", tn_im3name: "144377_3.jpg", tn_im4name: "144377_4.jpg", type: 0, nico_recommended: 2)
>>> MyStruct(tn_newsid: 144377, tn_midashi: "知ホーツク海の絶景が広がる", tn_name: "北海道立オホートキャンプ場てんとらんど", tn_ktel: "0152-45-27", tn_url: "", tn_kdo: 144.239526856306, tn_ido: 46.9880220633556, tn_im1name: "144377_1.jpg", tn_im2name: "144377_2.jpg", tn_im3name: "144377_3.jpg", tn_im4name: "144377_4.jpg", type: 0, nico_recommended: 0)

已获取 json 文件，因为 NSArray 仅包含第一个字符

Fetched json file as NSArray contains only the first character

arrays

json

dictionary

swift