将 JSON 对象层次结构反序列化为 Dictionary<string, object> 的层次结构 [英] Deserializing a JSON object hierarchy into a hierarchy of Dictionary<string, object>

问题描述

我在 .NET for WinRT (C#) 中，我想将 JSON 字符串反序列化为 Dictionary，其中字典value 可以稍后转换为实际类型.JSON 字符串可以包含对象层次结构，我也希望在 Dictionary<string, object> 中有子对象.

I'm in .NET for WinRT (C#) and I'd like to deserialize a JSON string to a Dictionary<string, object>, where the dictionary value can later be converted to the actual type. The JSON string can contain an object hierarchy and I'd like to have child objects in Dictionary<string, object> as well.

这是它应该能够处理的示例 JSON:

Here's a sample JSON it should be able to handle:

{
  "Name":"John Smith",
  "Age":42,
  "Parent":
  {
    "Name":"Brian Smith",
    "Age":65,
    "Parent":
    {
       "Name":"James Smith",
       "Age":87,
    }
  }
}

我尝试使用 DataContractJsonSerializer 这样做:

I tried with the DataContractJsonSerializer doing as so:

using (MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(json)))
{
    DataContractJsonSerializerSettings settings = new DataContractJsonSerializerSettings();
    settings.UseSimpleDictionaryFormat = true;

    DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(Dictionary<string, object>), settings);
    Dictionary<string, object> results = (Dictionary<string, object>)serializer.ReadObject(ms);
}

这实际上适用于第一级，但是 "Parent" 只是一个不能转换为 Dictionary 的对象::p>

This actually works fine for the first level, but then "Parent" is just an object which cannot be casted to a Dictionary<string, object>:

Dictionary<string, object> parent = (Dictionary<string, object>)results["Parent"];
Cannot cast 'results["Parent"]' (which has an actual type of 'object') to 'System.Collections.Generic.Dictionary<string,object>'

然后我尝试使用 Json.NET 但子对象是 JObject 本身是 IDictionary，这迫使我遍历整个层次结构并转换它们重新来过.

I then tried using Json.NET but child objects are JObject themselves being IDictionary<string, JToken>, which forces me to iterate through the full hierarchy and convert them over again.

有人知道如何使用现有的序列化程序解决这个问题吗?

Would someone know how to solve this problem using an existing serializer?

编辑

我使用 Dictionary<string, object> 因为我的对象因一个服务器调用而异(例如，"Id" 属性可能是 "id"、*"cust_id"* 或 "customerId" 取决于请求)并且由于我的应用程序不是唯一使用这些服务的应用程序，我无法更改它，在至少现在.

I'm using Dictionary<string, object> because my objects vary from one server call to another (e.g. the "Id" property might be "id", *"cust_id"* or "customerId" depending on the request) and as my app isn't the only app using those services, I can't change that, at least for now.

因此，我发现在这种情况下使用 DataContractAttribute 和 DataMemberAttribute 很不方便.相反，我想将所有内容存储在通用字典中，并有一个强类型属性Id"，它在字典中查找id"、cust_id"或customerId"，使其对 UI 透明.

Therefore, I found it inconvenient to use DataContractAttribute and DataMemberAttribute in this situation. Instead I'd like to store everything in a generic dictionary, and have a single strongly-typed property "Id" which looks for "id", "cust_id" or "customerId" in the dictionary making it transparent for the UI.

这个系统与 JSON.NET 配合得很好，但是如果服务器返回一个对象层次结构，子对象将作为 JObjects 存储在我的字典中，而不是另一个字典中.

This system works great with JSON.NET, however if ever the server returns an object hierarchy, sub-objects will be stored as JObjects in my dictionary instead of another dictionary.

总而言之，我正在寻找一个有效的系统来使用 WinRT 中可用的 JSON 序列化程序将对象层次结构转换为 Dictionary 的层次结构.

To sum-up, I'm looking for an efficient system to transform an object hierarchy into a hierarchy of Dictionary<string, object> using a JSON serializer available in WinRT.

推荐答案

我正在使用 JSON.NET 库和 ExpandoObject 类的组合在 WinRT 应用程序中解决同样的问题.该库能够很好地将 JSON 数据反序列化为实现 IDictionary 的 ExpandoObjects.ExpandoObject 的键值对的值很容易被视为另一个 ExpandoObject.

I'm addressing this same issue in a WinRT app using a combination of the JSON.NET library and the ExpandoObject class. The library is able to deserialize JSON data quite nicely into ExpandoObjects, which implement IDictionary. The value of an ExpandoObject's key-value pair may easily be treated as another ExpandoObject.

这是我使用的方法，适用于您的示例:

Here's the approach I used, adapted to your sample:

void LoadJSONData()
{
    string testData = "{ "Name":"John Smith", "Age":42, "Parent": { "Name":"Brian Smith", "Age":65, "Parent": { "Name":"James Smith", "Age":87, } } }";

    ExpandoObject dataObj = JsonConvert.DeserializeObject<ExpandoObject>(testData, new ExpandoObjectConverter());

    // Grab the parent object directly (if it exists) and treat as ExpandoObject
    var parentElement = dataObj.Where(el => el.Key == "Parent").FirstOrDefault();
    if (parentElement.Value != null && parentElement.Value is ExpandoObject)
    {
        ExpandoObject parentObj = (ExpandoObject)parentElement.Value;
        // do something with the parent object...
    }

    // Alternately, iterate through the properties of the expando
    foreach (var property in (IDictionary<String, Object>)dataObj)
    {
        if (property.Key == "Parent" && property.Value != null && property.Value is ExpandoObject)
        {
            foreach (var parentProp in (ExpandoObject)property.Value)
            {
                // do something with the properties in the parent expando
            }
        }
    }
}

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