显示外汇字典键/值对

Question

这是对上提出的问题的跟进。我需要一些帮助来显示汇率条目。我知道这是一个字典键/值，但我不确定如何从结构中提取每个字符串/双对。

这是从 API 收到的典型字符串格式：

{ 
  "rates": { "CAD": 1.5497, "HKD": 9.2404, "ISK":159.0 },
  "base": "EUR", 
  "date": "2020-11-27" 
}

struct RateResult: Codable {
    let rates: [String: Double]
    let base, date: String
}

struct ContentView: View {
    @State private var results = RateResult(rates: [:], base: "", date: "")
    
    var curr = "EUR"
    
    var body: some View {
        Text("Base Currency = \(results.base)")
        Text("Date = \(results.date)")
    
        List(results, id: \.results.rates) { item in
                   VStack(alignment: .leading) {
                    Text(results.rates[item.key])
                    Text(results.rates[item.value])
            }
        }
        .onAppear(perform: loadData)
    }
    func loadData() {
    }
}

Answer 1

要从字典中获取 key/value 对的数组，您可以使用 .map:

let dict = ["one": 1, "two": 2, "three": 3]
let pairs = dict.map { ([=10=], ) } // ex: [("one": 1"), ("three": 3), ("two": 2)]

因此，您可以在 List:

中使用相同的内容

List(results.rates.map { ([=11=], ) }, id: \.0) { currency, rate in
   VStack {
      Text(currency)
      Text("\(rate)")
   }
}

显示外汇字典键/值对

Displaying Foreign Exchange Dictionary Key / Value Pairs

swiftui

ios14