Question

与以下json对应的数据模型是什么？

df=pd.DataFrame({'col1':['x','y','z'],'col3':[[('ab','cv'), ('da','ndfds')],[('ab','cv')],[('dsfsa','sfa'), ('sd','sfag')]]})
l=[('ab','cv'),('da','ndfds')]

这是字典的字典所以我尝试了，

{ 
   dog:
   {
      type: "dog",
      logoLocation: "url1"
   },
   pitbull: 
   {
       type: "pitbull",
       logoLocation: "url2"
    }
}

但是它不起作用。有什么帮助吗？

Answer 1

您需要

let calcError2 filter (fcalc:'a -> float) (arr:'a array) =
    let subarr = arr |> Array.filter filter
    if Array.isEmpty subarr then Result.Error "array length 0" 
    else subarr |> Array.averageBy fcalc |> Result.Ok

更正json

struct Root: Codable {
    let dog, pitbull: Dog
}

struct Dog: Codable {
    let type, logoLocation: String  // or let logoLocation:URL
}

动态

只需在解码器中使用{ "dog": { "type": "dog", "logoLocation": "url1" }, "pitbull": { "type": "pitbull", "logoLocation": "url2" } }

[String:Dog]

Answer 2

我会跳过第一堂课，然后继续

class PhotoModel: Codable {
    var type: String
    var logoLocation: String
}

然后像字典一样对其进行解码

do {
    let decoder = JSONDecoder()
    let result = try decoder.decode([String: PhotoModel].self, from: data)
    result.forEach { (key,value) in
        print("Type: \(value.type), logo: \(value.logoLocation) (key: \(key))")
    }
} catch  {
    print(error)
}

输出

类型：狗，徽标：url1（键：狗）
类型：pitbull，徽标：url2（键：pitbull）

两个属性确实都是可选的，如果不是，我建议您删除?中任何不必要的PhotoModel（我确实如此）

使用JSONDecoder Swift进行解码

2 个答案: