Newtonsoft deserialize should be empty not null-CodePudding

When I deserialize the JSON string to a class, I need some of the properties to get an empty format, not null.

Today:

{
    "OrderResponse": {
        "ID": {
            "Content": "xxx"
        },
        "IssueDate": {
            "Content": "2022-07-07"
        },
        "IssueTime": {
            "Content": "14:42:07"
        },
        "OrderReference": {
            "ID": {
                "Content": "xxx"
            }
        },
        "SellerSupplierParty": {
            "PartyIdentification": null
        },
        "BuyerCustomerParty": {
            "PartyIdentification": null
        },...

As you can see both PartyIdentification is null.

I need it to be like this:

{
  "OrderResponse": {
    "ID": {
      "Content": "xxxx"
    },
    "IssueDate": {
      "Content": "2022-07-06"
    },
    "IssueTime": {
      "Content": "14:27:35"
    },
    "OrderReference": {
      "ID": {
        "Content": "OKNqIBEo"
      }
    },
    "BuyerCustomerParty": {
      "Party": {
        "PartyIdentification": {
          "ID": {}
        }
      }
    },
    "SellerSupplierParty": {
      "Party": {
        "PartyIdentification": {
          "ID": {}
        }
      }
    },...

The class definition looks like this:

public class SftiOrderResponse
    {
        public OrderResponse OrderResponse { get; set; }
    }

    public class OrderResponse
    {
        [JsonProperty(PropertyName = "ID")]
        public OrderId Id { get; set; }
        public IssueDate IssueDate { get; set; }
        public IssueTime IssueTime { get; set; }
        public OrderReference OrderReference { get; set; }
        public Party SellerSupplierParty { get; set; }
        public Party BuyerCustomerParty { get; set; }
        public IList<OrderLine> OrderLine { get; set; }
    }
        public class Party
        {
            [JsonProperty(DefaultValueHandling = DefaultValueHandling.Populate)]
            public PartyIdentification PartyIdentification { get; set; }
        }

        public class PartyIdentification
        {
            [JsonProperty(PropertyName = "ID")]
            public PartyIdentificationId Id { get; set; }
        }

        public class PartyIdentificationId : StringContent { }
public class StringContent
{
    public string Content { get; set; }
}

What is the best way to do it?

CodePudding user response：

The simplest way is to include a default value in your class. You can also create a custom JsonConverter.

CodePudding user response：

Newtonsoft.Json has a class called "JsonConvert"

If you call

JsonConvert.SerializeObject(data,  new JsonSerializerSettings()
{
   NullValueHandling = NullValueHandling.Ignore
}

Then it will not serialize out null values as shown

You can also set the option

DefaultValueHandling = DefaultValueHandling.Ignore

to not serialize defaults as well.

Using JsonSerializerSettings both works for serialization and deserialization

Update

If you initialize your strings to empty string -- then on deserialize, it will ignore the null values in the json file, and leave the strings as empty string

Answer 2:

You could also write a custom String converter inheriting off of JsonConverter

JsonConvert.SerializeObject(data,  new JsonSerializerSettings()
{
   Converters = new List<JsonConverter> { new PartyIdentification() }
}

public class PartyIdentificationConverter: JsonConverter
{
   public override bool CanConvert(Type objectType)
   {
     return typeof(PartyIdentificationConverter).IsAssignableFrom(objectType);
   }

   public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
   {
      reader.Read();
      var p = (PartyIdentificationConverter)reader.Value;

      return p!= null ? p: new PartyIdentificationConverter(); 
   }

   public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
   {
      writer.WriteValue(value);
   }
}