如何在 swift 4.1 和 xcode 9.3 中使用 JSONDecoder 解码嵌套的 JSON 数组和对象？
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【中文标题】如何在 swift 4.1 和 xcode 9.3 中使用 JSONDecoder 解码嵌套的 JSON 数组和对象？【英文标题】：How to decode nested JSON array and object with JSONDecoder in swift 4.1 and xcode 9.3? 【发布时间】：2018-05-17 05:23:19 【问题描述】：我是 iOS 新手，我在解码包含许多嵌套数组和对象的嵌套 JSON 文件时遇到问题。我正在使用 JSONDecoder 进行解码，但在某处我出错或解码不正确。
我的解码器是
let myOrder = try JSONDecoder().decode(MyOrder.self, from: data!)
for items in myOrder.OrderDetials
self.orders.append(MyOrders(order_id: items.order_id!, order_ref_number: items.order_ref_number!, cust_mob: items.cust_mob!, store_name: items.store_name!, store_id: items.store_id!, order_details: items.order_details!, order_amount: items.order_amount!, order_status: items.order_status!, order_status_remark: items.order_status_remark!, order_place_at: items.order_place_at!, order_status_change_at: items.order_status_change_at!))
print(items.cust_mob!)
print(myOrder)
它抛出的错误是
typeMismatch(Swift.Array<Any>, Swift.DecodingError.Context(codingPath: [CodingKeys(stringValue: "OrderDetials", intValue: nil), _JSONKey(stringValue: "Index 0", intValue: 0), CodingKeys(stringValue: "order_details", intValue: nil)], debugDescription: "Expected to decode Array<Any> but found a string/data instead.", underlyingError: nil))
我的结构是
struct MyOrder: Decodable
var OrderDetials: [OrderDetails]
struct OrderDetails: Decodable
var order_id: String?
var order_ref_number: String?
var cust_mob: String?
var store_name: String?
var store_id: String?
var order_details: OrderItems?
var order_amount: String?
var order_status: String?
var order_status_remark: String?
var order_place_at: String?
var order_status_change_at: String?
struct OrderItems: Decodable
var allorder: [AllOrder]
var TaxDetials: [TaxDetails]
struct AllOrder: Decodable
var date_time: String?
var item: String?
var name: String?
struct TaxDetails: Decodable
var tax_per: String?
var tax_name: String?
和DataModel类
class MyOrders
var order_id: String
var order_ref_number: String
var cust_mob: String
var store_name: String
var store_id: String
var order_details: OrderItems?
var order_amount: String
var order_status: String
var order_status_remark: String
var order_place_at: String
var order_status_change_at: String?
init(order_id: String, order_ref_number: String, cust_mob: String, store_name: String, store_id: String, order_details: OrderItems?, order_amount: String, order_status: String, order_status_remark: String, order_place_at: String, order_status_change_at: String?)
self.order_id = order_id
self.order_ref_number = order_ref_number
self.cust_mob = cust_mob
self.store_name = store_name
self.store_id = store_id
self.order_details = order_details
self.order_amount = order_amount
self.order_status = order_status
self.order_status_remark = order_status_remark
self.order_place_at = order_place_at
self.order_status_change_at = order_status_change_at
class MyItems
var item: String
var name: String
var price: String
init(item: String, name: String, price: String)
self.item = item
self.name = name
self.price = price
我的 JSON 是
"OrderDetials": [
"order_id": "11",
"order_ref_number": "MM1525235813",
"cust_mob": "9958324531",
"store_name": "Moti mahal",
"store_id": "1",
"order_details": "'allorder':[\"date_time\":\"\",\"item\":\"2\",\"name\":\"CHICKN ROLL\",\"price\":\"360\"]\"TaxDetials\":[\"tax_per\":\"5\",\"tax_name\":\"CGST & SGST\"]",
"order_amount": "378.0",
"order_status": "1",
"order_status_remark": "New_Order_Place",
"order_place_at": "2018-05-02 10:06:53",
"order_status_change_at": null
]
请有人告诉我如何正确解码或我需要对结构进行哪些更改。
【问题讨论】：
您的“order_details”键的值是字符串，您的结构将其视为数组。您必须根据定义的结构更改“order_details”键的值才能使其工作 您的 order_details 包含 JSON 之类的结构而不是字符串 我试过这样做：“var order_details: String?”还有这个：“var order_details：[OrderItems]？”两者都给出相同的错误。 @Vikky var order_details: 字符串？正在工作 查看这篇文章，它解释得很好medium.com/@nimjea/json-parsing-in-swift-2498099b78f 【参考方案1】：OrderDetials 是 Array of Dictionary [[String: String?]] ，而您的 Initial 响应是 Dictionary 也是 order_details 是 Wrong json String 而不是 Dictionary ，所以我们将它解析为字符串，在 Codable 每个字典 @ 987654329@ 转换为Struct 或Class 和[] 是Array
型号：
import Foundation
struct Initial: Codable
let orderDetials: [OrderDetial]
enum CodingKeys: String, CodingKey
case orderDetials = "OrderDetials"
struct OrderDetial: Codable
let orderID, orderRefNumber, custMob, storeName: String
let storeID, orderDetails, orderAmount, orderStatus: String
let orderStatusRemark, orderPlaceAt: String
let orderStatusShangeAt:String?
enum CodingKeys: String, CodingKey
case orderID = "order_id"
case orderRefNumber = "order_ref_number"
case custMob = "cust_mob"
case storeName = "store_name"
case storeID = "store_id"
case orderDetails = "order_details"
case orderAmount = "order_amount"
case orderStatus = "order_status"
case orderStatusRemark = "order_status_remark"
case orderPlaceAt = "order_place_at"
case orderStatusShangeAt = "order_status_change_at"
// MARK: Convenience initializers
extension Initial
init(data: Data) throws
self = try JSONDecoder().decode(Initial.self, from: data)
这样使用：
if let initial = try? Initial.init(data: data)
for item in initial.orderDetials
print(item.orderAmount)
print(item.orderDetails) // here is Wrong format from your Server API
Order_details 错误
'allorder':["date_time":"","item":"2","name":"CHICKN ROLL","price":"360"]"TaxDetials":["tax_per":"5","tax_name":"CGST & SGST"]
【讨论】：
现在我得到了 orderDetails 作为字符串。我需要使用 JSONSerialization 来访问其中的数据还是 JSONDecoder 会自动执行此操作？ 是的，你可以再次解析它，但它也错误地检查了这个'allorder'不是“allorder”
谢谢，实际上 JSON 是由 API 团队生成的，android 团队也使用相同的 JSON 并且它在那里工作，所以我必须使用相同的 JSON。
不，和服务器上的一样。我已经仔细检查了。
好的，所以你的后端开发人员错了，你可以和你的android开发人员核实一下，他可能用任何其他方式格式化这个字符串，但是这个错误的Json和错误的json字符串以上是关于如何在 swift 4.1 和 xcode 9.3 中使用 JSONDecoder 解码嵌套的 JSON 数组和对象？的主要内容，如果未能解决你的问题，请参考以下文章