如何将json字典序列化/反序列化为数组

Question

需要将C＃字典序列化和反序列化为JSON数组。 我还想使用数组索引表示法从powershell读取JSON。

默认情况下，JSON格式为：

{
 "defaultSettings": {
  "applications": {
   "Apollo": {
    "environments": {
      "DEV": {
        "dbKeyTypes": {
          "DmkPassword": "AEikOooIuGxXC9UBJQ3ckDj7Q126tB06",
          "SymmetricKeySource": "bTU7XOAYA2FFifmiBUggu99yHxX3Ftds"
        }
      },
      "TST": {
        "dbKeyTypes": {
          "DmkPassword": "AEikOooIuGxXC9UBJQ3ckDj7Q126tB06",
          "SymmetricKeySource": "bTU7XOAYA2FFifmiBUggu99yHxX3Ftds"
        }
      }
    }
  },
  "Gemini": {
    "environments": {
      "DEV": {
        "dbKeyTypes": {
          "DmkPassword": "AEikOooIuGxXC9UBJQ3ckDj7Q126tB06",
          "SymmetricKeySource": "bTU7XOAYA2FFifmiBUggu99yHxX3Ftds"
        }
      },
      "TST": {
        "dbKeyTypes": {
          "DmkPassword": "AEikOooIuGxXC9UBJQ3ckDj7Q126tB06",
          "SymmetricKeySource": "bTU7XOAYA2FFifmiBUggu99yHxX3Ftds"
        }
      }
    }
   }
  }
 }
}

这在.Net Core中使用默认的json阅读器很有效，但它不允许我在PowerShell中使用数组索引表示法。

相反，我正在寻找的是：

{
 "defaultSettings": {
  "applications": [
   {
     "Apollo": {
      "environments": [
        {
          "DEV": {
            "dbKeyTypes": [
              {
                "DmkPassword": "AEikOooIuGxXC9UBJQ3ckDj7Q126tB06"
              },
              {
                "SymmetricKeySource": "bTU7XOAYA2FFifmiBUggu99yHxX3Ftds"
              }
            ]
          }
        },
        {
          "TST": {
            "dbKeyTypes": [
              {
                "DmkPassword": "AEikOooIuGxXC9UBJQ3ckDj7Q126tB06"
              },
              {
                "SymmetricKeySource": "bTU7XOAYA2FFifmiBUggu99yHxX3Ftds"
              }
            ]
          }
        }
      ]
    }
  },
  {
    "Gemini": {
      "environments": [
        {
          "DEV": {
            "dbKeyTypes": [
              {
                "DmkPassword": "AEikOooIuGxXC9UBJQ3ckDj7Q126tB06"
              },
              {
                "SymmetricKeySource": "bTU7XOAYA2FFifmiBUggu99yHxX3Ftds"
              }
            ]
          }
        },
        {
          "TST": {
            "dbKeyTypes": [
              {
                "DmkPassword": "AEikOooIuGxXC9UBJQ3ckDj7Q126tB06"
              },
              {
                "SymmetricKeySource": "bTU7XOAYA2FFifmiBUggu99yHxX3Ftds"
              }
            ]
          }
        }
      ]
    }
   }
  ]
 }
}

我正在使用从Serializing Dictionary <string，string>到“name”数组的WriteJson部分：“value”

这很好用; 但是，当然因为没有实现ReadJson()方法，所以它不会读取。 顺便说一句，为了获得上面所需的json格式，我将链接中的CustomDictionaryConverter修改为：

writer.WritePropertyName(key.ToString());
//writer.WriteValue(key);
//writer.WritePropertyName("value");
serializer.Serialize(writer, valueEnumerator.Current);

实现背后的类是：

public enum DeploymentEnvironment { DEV = 1, TST = 2 }
public enum TargetApplication { Apollo = 1, Gemini = 2 }
public enum DbKeyType { DmkPassword = 1, SymmetricKeySource = 2 }

public class DeploymentSettings
{
    [JsonProperty("defaultSettings")]
    public DefaultSettings DefaultSettings { get; set; }
    public DeploymentSettings()
    {
        DefaultSettings = new DefaultSettings();
    }
}

public partial class DefaultSettings
{
    [JsonProperty("applications")]
    public Dictionary<TargetApplication, ApplicationContainer> Applications { get; set; }

    public DefaultSettings()
    {
        Applications = new Dictionary<TargetApplication, ApplicationContainer>();
    }
}

public partial class ApplicationContainer
{
    [JsonProperty("environments")]
    public Dictionary<DeploymentEnvironment, EnvironmentContainer> Environments { get; set; }
    public ApplicationContainer()
    {
        Environments = new Dictionary<DeploymentEnvironment, EnvironmentContainer>();
    }
}

public partial class EnvironmentContainer
{
    [JsonProperty("dbKeyTypes")]
    public Dictionary<DbKeyType, string> DbKeyTypes { get; set; }

    public EnvironmentContainer()
    {
        DbKeyTypes = new Dictionary<DbKeyType, string>();
    }
}

我按如下方式序列化对象： var json = JsonConvert.SerializeObject(ds, Formatting.Indented, new CustomDictionaryConverter());

如上所述，序列化工作，但我需要帮助编写ReadJson()方法，以便能够反序列化。

Answer 1

您可以将CustomDictionaryConverter扩展为读取和写入，如下所示：

public class CustomDictionaryConverter : JsonConverter
{
    // Adapted from CustomDictionaryConverter from this answer https://stackoverflow.com/a/40265708
    // To https://stackoverflow.com/questions/40257262/serializing-dictionarystring-string-to-array-of-name-value
    // By Brian Rogers https://stackoverflow.com/users/10263/brian-rogers

    sealed class InconvertibleDictionary : Dictionary<object, object>
    {
        public InconvertibleDictionary(DictionaryEntry entry)
            : base(1)
        {
            this[entry.Key] = entry.Value;
        }
    }

    public override bool CanConvert(Type objectType)
    {
        return typeof(IDictionary).IsAssignableFrom(objectType) && objectType != typeof(InconvertibleDictionary);
    }

    public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
    {
        // Lazy evaluation of the enumerable prevents materialization of the entire collection of dictionaries at once.
        serializer.Serialize(writer,  Entries(((IDictionary)value)).Select(p => new InconvertibleDictionary(p)));
    }

    public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
    {
        if (reader.MoveToContentAndAssert().TokenType == JsonToken.Null)
            return null;
        var dictionary = existingValue ?? serializer.ContractResolver.ResolveContract(objectType).DefaultCreator();
        switch (reader.TokenType)
        {
            case JsonToken.StartObject:
                serializer.Populate(reader, dictionary);
                return dictionary;

            case JsonToken.StartArray:
                {
                    while (true)
                    {
                        switch (reader.ReadToContentAndAssert().TokenType)
                        {
                            case JsonToken.EndArray:
                                return dictionary;

                            case JsonToken.StartObject:
                                serializer.Populate(reader, dictionary);
                                break;

                            default:
                                throw new JsonSerializationException(string.Format("Unexpected token {0}", reader.TokenType));
                        }
                    }
                }

            default:
                throw new JsonSerializationException(string.Format("Unexpected token {0}", reader.TokenType));
        }
    }

    static IEnumerable<DictionaryEntry> Entries(IDictionary dict)
    {
        foreach (DictionaryEntry entry in dict)
            yield return entry;
    }
}

public static partial class JsonExtensions
{
    public static JsonReader ReadToContentAndAssert(this JsonReader reader)
    {
        return reader.ReadAndAssert().MoveToContentAndAssert();
    }

    public static JsonReader MoveToContentAndAssert(this JsonReader reader)
    {
        if (reader == null)
            throw new ArgumentNullException();
        if (reader.TokenType == JsonToken.None)       // Skip past beginning of stream.
            reader.ReadAndAssert();
        while (reader.TokenType == JsonToken.Comment) // Skip past comments.
            reader.ReadAndAssert();
        return reader;
    }

    public static JsonReader ReadAndAssert(this JsonReader reader)
    {
        if (reader == null)
            throw new ArgumentNullException();
        if (!reader.Read())
            throw new JsonReaderException("Unexpected end of JSON stream.");
        return reader;
    }
}

然后，您可以使用以下设置对DeploymentSettings进行序列化和反序列化：

var settings = new JsonSerializerSettings
{
    Converters = { new CustomDictionaryConverter(), new StringEnumConverter() }
};

var ds = JsonConvert.DeserializeObject<DeploymentSettings>(json, settings);

var json2 = JsonConvert.SerializeObject(ds, Formatting.Indented, settings);

笔记：

• 此版本的转换器避免将整个字典加载到ReadJson()或WriteJson()的临时JArray层次结构中，而是直接从JSON流流式传输到JSON流。

• 由于序列化程序现在用于直接序列化单个字典条目， StringEnumConverter需要StringEnumConverter才能正确命名键。 （如果您在任何地方使用这样的字典，使用序列化程序还可以确保数字或DateTime键正确国际化。）

• 因为Json.NET支持注释，所以转换器会检查并跳过它们，这会增加复杂性。 （我希望有一种方法可以让JsonReader无声地跳过评论。）

演示在这里小提琴。