Reference Loop Handling Ignore not working on Asp.Net Core 3.0 Preview 3

Question

I have been beating my head against a wall with this one, trying to find out why it won\'t work. I haven\'t been able to find anything on why it won\'t work, so I am asking here

Answer 1

As explained in detail here as part of ASP.NET Core 3.0, the team moved away from including Newtonsoft.Json by default.

You probably need to install Microsoft.AspNetCore.Mvc.NewtonsoftJson and use (note, I'm using .AddNewtonsoftJson() chained with .AddControllers()) something similar:

services.AddControllers()
    .AddNewtonsoftJson(x =>
            {
                x.SerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;
            });

Answer 2

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

https://docs.microsoft.com/en-us/aspnet/core/migration/22-to-30?view=aspnetcore-3.0&tabs=visual-studio#jsonnet-support