Question

我有一个从服务器获取一些JSON数据的应用，如下所示：

"operationsInfo": {
    "bill": {
        "activeProviders": [
              {
                "max": 50,
                "min": 10,
                "name": "name1"
              },
              {
                "max": 50,
                "min": 10,
                "name": "name2"
              }
         ]
    },
    "pin": {
        "activeProviders": [
              {
                "max": 50,
                "min": 10,
                "name": "name3"
              },
              {
                "max": 50,
                "min": 10,
                "name": name4
              }
        ]
    }
}

如何使用快速可解码协议反序列化此JSON数据？我的自定义对象如下：

struct operationList: Decodable {

    let name: String
    let action: String
    let min, max: Int
}

operationList对象中的操作值必须等于“ bill”或“ pin”。最后，我想在解码JSON数据时获得一个operationList对象类型的数组，例如：

let operationListArray = [operationList1，operationList2，operationList3，operationList4] operationList1.action =“ bill”，operationList1.max = 50，operationList1.name =“ name1” operationList2.action =“ bill”，operationList2.max = 50，operationList2.name =“ name2” operationList3.action =“ pin”，operationList3.max = 50，operationList3.name =“ name3” operationList4.action =“ pin”，operationList4.max = 50，operationList4.name =“ name4”

我已经看到其他类似的答案，例如：How to decode a nested JSON struct with Swift Decodable protocol? 但是我的问题是我如何将“ bill”或“ pin”放在操作值中，并且将来可能将新的键值（例如“ transfer”（例如“ pin”或“ bill”）添加到JSON数据中。

Answer 1

正如@rmaddy在评论中提到的那样，您要分两个步骤进行操作。

首先，创建一个与您的JSON格式匹配的结构并将其解码：

struct Response: Decodable {
    let operationsInfo: [String: Providers]
}

struct Providers: Decodable {
    let activeProviders: [Provider]
}

struct Provider: Decodable {
    let name: String
    let min: Int
    let max: Int
}

let response = try JSONDecoder().decode(Response.self, from: data)

然后，声明一个结构，该结构表示您希望数据使用的格式并进行映射：

struct ProviderAction {
    let action: String
    let provider: Provider
}

let actions: [ProviderAction] = response.operationsInfo.map { action, providers in
    providers.activeProviders.map { ProviderAction(action: action, provider: $0) }
}.flatMap { $0 }

如何使用快速可解码协议解析嵌套的JSON数据？

1 个答案: