How to store JSON in an entity field with EF Core?

Question

I am creating a reusable library using .NET Core (targeting .NETStandard 1.4) and I am using Entity Framework Core (and new to both). I have an entity class that looks like

Answer 1

// DbContext

  protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            var entityTypes = modelBuilder.Model.GetEntityTypes();
            foreach (var entityType in entityTypes)
            {
                foreach (var property in entityType.ClrType.GetProperties().Where(x => x != null && x.GetCustomAttribute() != null))
                {
                    modelBuilder.Entity(entityType.ClrType)
                        .Property(property.PropertyType, property.Name)
                        .HasJsonConversion();
                }
            }

            base.OnModelCreating(modelBuilder);
        }

Create an attribute to handle the properties of the entities.

public class HasJsonConversionAttribute : System.Attribute
    {

    }

Create extention class to find Josn properties

    public static class ValueConversionExtensions
    {
        public static PropertyBuilder HasJsonConversion(this PropertyBuilder propertyBuilder)
        {
            ParameterExpression parameter1 = Expression.Parameter(propertyBuilder.Metadata.ClrType, "v");

            MethodInfo methodInfo1 = typeof(Newtonsoft.Json.JsonConvert).GetMethod("SerializeObject", types: new Type[] { typeof(object) });
            MethodCallExpression expression1 = Expression.Call(methodInfo1 ?? throw new Exception("Method not found"), parameter1);

            ParameterExpression parameter2 = Expression.Parameter(typeof(string), "v");
            MethodInfo methodInfo2 = typeof(Newtonsoft.Json.JsonConvert).GetMethod("DeserializeObject", 1, BindingFlags.Static | BindingFlags.Public, Type.DefaultBinder, CallingConventions.Any, types: new Type[] { typeof(string) }, null)?.MakeGenericMethod(propertyBuilder.Metadata.ClrType) ?? throw new Exception("Method not found");
            MethodCallExpression expression2 = Expression.Call(methodInfo2, parameter2);

            var converter = Activator.CreateInstance(typeof(ValueConverter<,>).MakeGenericType(typeof(List), typeof(string)), new object[]
                {
                    Expression.Lambda( expression1,parameter1),
                    Expression.Lambda( expression2,parameter2),
                    (ConverterMappingHints) null
                });

            propertyBuilder.HasConversion(converter as ValueConverter);

            return propertyBuilder;
        }
    }

Entity example

 public class Attribute
    {
        [Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int Id { get; set; }
        public string Name { get; set; }

        [HasJsonConversion]
        public List Values { get; set; }
    }

    public class AttributeValue
    {
        public string Value { get; set; }
        public IList Translations { get; set; }
    }

    public class AttributeValueTranslation
    {
        public string Translation { get; set; }

        public string CultureName { get; set; }
    }

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