Unable to decode a JSON file-CodePudding

I am learning Swift/SwiftUI and I faced a problem. The Xcode's writing this:

"Expected to decode Dictionary<String, CurrencyData> but found an array instead."

Here's a code:

import Foundation
import SwiftUI


struct CurrencyData: Codable {
    let r030: Int
    let txt: String
    let rate: Double
    let cc: String
    let exchangedate: String
}

typealias Currency = [String: CurrencyData]

import SwiftUI

 class API: ObservableObject {
    
     @Published var currencyCode: [String] = []
     @Published var priceRate: [Double] = []
     @Published var exchangeDate: [String] = []
     
     init() {
         fetchdata { (currency) in
             switch currency {
             case .success(let currency):
                 currency.forEach { (c) in
                     DispatchQueue.main.async {
                         self.currencyCode.append(c.value.cc)
                         self.priceRate.append(c.value.rate)
                         self.exchangeDate.append(c.value.exchangedate)
                }
             }
             case(.failure(let error)):
                 print("Unable to featch the currencies data", error)
         }
     }
}

     func fetchdata(completion: @escaping (Result<Currency,Error>) -> ()) {
         guard let url = URL(string: "https://bank.gov.ua/NBUStatService/v1/statdirectory/exchange?json") else { return }
         URLSession.shared.dataTask(with: url) { data, responce, error in
             if let error = error {
                 completion(.failure(error))
                 return
             }
             
             guard let safeData = data else { return }
             
             do {
                 let currency = try JSONDecoder().decode(Currency.self, from: safeData)
                 completion(.success(currency))
             }
             catch {
                 completion(.failure(error))
             }
         }
         .resume()
     }
 }

CodePudding user response：

Change the type to correctly decode what you receive ( an array obviously )

This should work, but we can't answer for sure since we have no idea of the data. An attached json sample could help.

typealias Currency = [CurrencyData]

CodePudding user response：

Change the exchangeDate in your CurrencyData model to exchangedate which need to match exactly the same as api response. It was case sensitive.