Showing posts with label Serialize. Show all posts
Showing posts with label Serialize. Show all posts

Thursday, May 14, 2020

How to ignore property conditionally during JSON serialization

Consider i have class Employer, i want serialize this class to json string and need ignore some properties conditionally. For ex: in my example, i want to include address1 and address2 only if it has valid values


  public class Employer
    {
 public int id { get; set; }

        public string name { get; set; }
       
 public string ssn { get; set; }

        public string address1 { get; set; }

        public string address2 { getset; }
   }



Declare some values


Employer employer = new Employer(){ … address1 = "some value", address2 = null };


Now serialize it for json string


var jsonstring = JsonConvert.SerializeObject(employer,
                       Newtonsoft.Json.Formatting.None,
                       new JsonSerializerSettings
                       {
                           
                       });

Here you will get all the properties.

Now lets see how to ignore the properties conditionally, you can choose either one of these options.

Option 1: Use ShouldSerialize property inside class itself like below. But you need add individual shouldSerialize property for each class property.

  public class Employer
    {
 public int id { get; set; }

        public string name { get; set; }
       
 public string ssn { get; set; }

        public string address1 { get; set; }

        public string address2 { get; set; }

        public bool ShouldSerializeaddress1()
        {
            // don't serialize if it is null or empty or add any your custom conditions
            return !string.IsNullOrEmpty(address1);
        }
        public bool ShouldSerializeaddress2()
        {
            // don't serialize if it is null or empty or add any your custom conditions
            return !string.IsNullOrEmpty(address2);
        }

   }


Option 2: Instead creating multiple ShouldSerialize property inside class, we can create ContractResolver and add it in Json serialization as below,

Create Resolver Class,

using Newtonsoft.Json;
using Newtonsoft.Json.Serialization;
using System.Linq;
using System.Reflection;
...

  public class EmployerShouldSerializeContractResolver : DefaultContractResolver
    {
        public new static readonly EmployerShouldSerializeContractResolver Instance = new EmployerShouldSerializeContractResolver();

        protected override JsonProperty CreateProperty(MemberInfo member, MemberSerialization memberSerialization)
        {
            JsonProperty property = base.CreateProperty(member, memberSerialization);

            if (property.DeclaringType == typeof(Employer))
            {
                property.ShouldSerialize =
                    instance =>
                    {
                        //ignore default values
                        return instance.GetType().GetProperty(member.Name).GetValue(instance, null) != property.DefaultValue;
                    };
            }

            return property;
        }

    }


Include it in JSON serialization,

var jsonstring = JsonConvert.SerializeObject(employer,
                       Newtonsoft.Json.Formatting.None,
                       new JsonSerializerSettings
                       {
                           ContractResolver = new EmployerShouldSerializeContractResolver()
                       });