我在使用json.net序列化数据时遇到了一个奇怪的问题。主要是，我试图将传出的json中的“Key”和“Value”名称重命名为更具描述性的名称。具体来说，我希望将与IRequest相关的“Key”称为“Request”，将IQuoteTimeSeries的“Value”称为“DataSeries”
注意，这不会反序列化。它仅用于网页上的数据分析。
我正在序列化的数据存储库对象是Dictionary<IRequest, IQuoteTimeSeries>对象。 IRequest表示对数据的特定请求，IQuoteTimeSeries是包含返回数据的对象SortedDictionary<DateTime, IQuote>。这是按时间戳排序的一系列数据。在这个例子中，为了简洁起见，我在TimeSeries中只有一个项目，但在大多数情况下会有很多项目。
所有内容都需要组织在一起，序列化并发送给JavaScript使用。
以下是这些对象的基本代码;
[JsonArray]
public class QuoteRepository : Dictionary<IRequest, IQuoteTimeSeries>, IQuoteRepository
{
public QuoteRepository() { }
public void AddRequest(IRequest request)
{
if (!this.ContainsKey(request))
{
IQuoteTimeSeries tSeries = new QuoteTimeSeries(request);
this.Add(request, tSeries);
}
}
public void AddQuote(IRequest request, IQuote quote)
{
if (!this.ContainsKey(request))
{
QuoteTimeSeries tSeries = new QuoteTimeSeries(request);
this.Add(request, tSeries);
}
this[request].AddQuote(quote);
}
IEnumerator<IQuoteTimeSeries> Enumerable<IQuoteTimeSeries>.GetEnumerator()
{
return this.Values.GetEnumerator();
}
}
报价时间序列如下所示;
[JsonArray]
public class QuoteTimeSeries: SortedDictionary<DateTime, IQuote>, IQuoteTimeSeries
{
public QuoteTimeSeries(IRequest request)
{
Request = request;
}
public IRequest Request { get; }
public void AddQuote(IQuote quote)
{
this[quote.QuoteTimeStamp] = quote;
}
public void MergeQuotes(IQuoteTimeSeries quotes)
{
foreach (IQuote item in quotes)
{
this[item.QuoteTimeStamp] = item;
}
}
IEnumerator<IQuote> IEnumerable<IQuote>.GetEnumerator()
{
return this.Values.GetEnumerator();
}
}
用于序列化的代码非常简单：
IQuoteRepository quotes = await requests.GetDataAsync();
JsonSerializerSettings settings = new JsonSerializerSettings
{
ContractResolver = QuoteRepositoryContractResolver.Instance,
NullValueHandling = NullValueHandling.Ignore
};
return Json<IQuoteRepository>(quotes, settings);
我添加了一份合同解析程序，旨在覆盖财产写作。正在命中property.PropertyName =代码并且正在更改属性名称，但输出JSON不受影响。
public class QuoteRepositoryContractResolver : DefaultContractResolver
{
public static readonly QuoteRepositoryContractResolver Instance = new QuoteRepositoryContractResolver();
protected override JsonProperty CreateProperty(MemberInfo member, MemberSerialization memberSerialization)
{
JsonProperty property = base.CreateProperty(member, memberSerialization);
if (property.DeclaringType == typeof(KeyValuePair<IRequest, IQuoteTimeSeries>))
{
if (property.PropertyName.Equals("Key", StringComparison.OrdinalIgnoreCase))
{
property.PropertyName = "Request";
}
else if (property.PropertyName.Equals("Value", StringComparison.OrdinalIgnoreCase))
{
property.PropertyName = "Data";
}
}
else if (property.DeclaringType == typeof(KeyValuePair<DateTime, IQuote>))
{
if (property.PropertyName.Equals("Key", StringComparison.OrdinalIgnoreCase))
{
property.PropertyName = "TimeStamp";
}
else if (property.PropertyName.Equals("Value", StringComparison.OrdinalIgnoreCase))
{
property.PropertyName = "Quote";
}
}
return property;
}
}
输出JSON是奇数。 Key和Value项完全没有变化，即使我在代码中更改了它们的名称。
[
{
"Key": {
"QuoteDate": "2016-05-12T00:00:00-04:00",
"QuoteType": "Index",
"Symbol": "SPY",
"UseCache": true
},
"Value": [
{
"Key": "2016-05-11T16:00:01-04:00",
"Value": {
"Description": "SPDR S&P 500",
"High": 208.54,
"Low": 206.50,
"Change": -1.95,
"ChangePer": -0.94,
"Price": 206.50,
"QuoteTimeStamp": "2016-05-11T16:00:01-04:00",
"Symbol": "SPY"
}
}
]
},
{
"Key": {
"QuoteDate": "2016-05-12T00:00:00-04:00",
"QuoteType": "Stock",
"Symbol": "GOOG",
"UseCache": true
},
"Value": [
{
"Key": "2016-05-11T16:00:00-04:00",
"Value": {
"Description": "Alphabet Inc.",
"High": 724.48,
"Low": 712.80,
"Change": -7.89,
"ChangePer": -1.09,
"Price": 715.29,
"QuoteTimeStamp": "2016-05-11T16:00:00-04:00",
"Symbol": "GOOG"
}
}
]
}
]
有谁知道如何正确更改“钥匙”和“价值”物品？
答案 0 :(得分：4)
解决此问题的一种方法是为基于字典的类使用自定义JsonConverter。代码实际上非常简单。
public class CustomDictionaryConverter<K, V> : JsonConverter
{
private string KeyPropertyName { get; set; }
private string ValuePropertyName { get; set; }
public CustomDictionaryConverter(string keyPropertyName, string valuePropertyName)
{
KeyPropertyName = keyPropertyName;
ValuePropertyName = valuePropertyName;
}
public override bool CanConvert(Type objectType)
{
return typeof(IDictionary<K, V>).IsAssignableFrom(objectType);
}
public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
{
IDictionary<K, V> dict = (IDictionary<K, V>)value;
JArray array = new JArray();
foreach (var kvp in dict)
{
JObject obj = new JObject();
obj.Add(KeyPropertyName, JToken.FromObject(kvp.Key, serializer));
obj.Add(ValuePropertyName, JToken.FromObject(kvp.Value, serializer));
array.Add(obj);
}
array.WriteTo(writer);
}
public override bool CanRead
{
get { return false; }
}
public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
{
throw new NotImplementedException();
}
}
当需要序列化时，请将转换器添加到JsonSerializerSettings，如下所示：
JsonSerializerSettings settings = new JsonSerializerSettings
{
Converters = new List<JsonConverter>
{
new CustomDictionaryConverter<IRequest, IQuoteTimeSeries>("Request", "Data"),
new CustomDictionaryConverter<DateTime, IQuote>("TimeStamp", "Quote")
},
Formatting = Formatting.Indented
};
string json = JsonConvert.SerializeObject(repo, settings);
答案 1 :(得分：-1)
将字典从compile 'com.jakewharton:butterknife:8.0.1'
apt 'com.jakewharton:butterknife-compiler:8.0.1'
转换为Dictionary<IRequest, IQuoteTimeSeries>也应该有效。