JSON.NET Error Self referencing loop detected for type

Question

I tried to serialize POCO class that was automatically generated from Entity Data Model .edmx and when I used

JsonConvert.SerializeObject 

Answer 1

If you're using .NET Core 2.x, update your ConfigureServices section in Startup.cs

https://docs.microsoft.com/en-us/ef/core/querying/related-data#related-data-and-serialization

    public void ConfigureServices(IServiceCollection services)
    {
    ...

    services.AddMvc()
        .AddJsonOptions(
            options => options.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore
        );

    ...
    }

If you're using .NET Core 3.x without MVC, it would be:

services.AddControllers()
  .AddNewtonsoftJson(options =>
      options.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore
   );

This reference loop handling is almost mandatory if you're using Entity Framework and database-first design pattern.