如何在 Swift 中打印我的 JSON 文件中的国家/地区值？

Question

我知道这可能是一个简单的答案，但对我来说很难。我有一个 Swift JSON 文件成功加载到我的 UserData 变量中。但我想从该数据集中获取一个值。我收到错误：“[UserData]”类型的值没有成员 'state'

[
  {
    "state":"Alaska",
    "latitude":61.3850,
    "longitude":-152.2683,
    "stateTax":"7%"
  },
  {
    "state":"Alabama",
    "latitude":32.7990,
    "longitude":-86.8073,
    "stateTax":"13.5%"
  },
  {
    "state":"Arkansas",
    "latitude":34.9513,
    "longitude":-92.3809,
    "stateTax":"11.625%"
  }
]

我的数据集UserData：

[LoadFromJSON.UserData(state: "Alaska", latitude: 61.385, longitude: -152.2683, stateTax: "7%"), LoadFromJSON.UserData(state: "Alabama", latitude: 32.799, longitude: -86.8073, stateTax: "13.5%"), LoadFromJSON.UserData(state: "Arkansas", latitude: 34.9513, longitude: -92.3809, stateTax: "11.625%")]

我的代码和错误行：

 do {
                let data =  try Data(contentsOf: fileLocation)
                let jsonDecoder = JSONDecoder()
                let dataFromJson = try jsonDecoder.decode([UserData].self, from: data)
                
                self.userData = dataFromJson
                
                print(userData)
                print(dataFromJson.state)  // Value of type '[UserData]' has no member 'state'
                
            } catch {
                print(error)
            }

Answer 1

dataFromJson是UserData的数组，所以需要这样迭代


do {
                let data =  try Data(contentsOf: fileLocation)
                let jsonDecoder = JSONDecoder()
                let dataFromJson = try jsonDecoder.decode([UserData].self, from: data)
                
                self.userData = dataFromJson
                dataFromJson.forEach{ user in

                    print(user.state)

                }
                
                print(userData)
                
                
            } catch {
                print(error)
            }

如何在 Swift 中打印我的 JSON 文件中的国家/地区值？

How can I print the country value from my JSON file in Swift?

xcode

swift