Setting JsonConvert.DefaultSettings asp net core 2.0 not working as expected

问题

I have following code inside Startup.cs and expecting it to override default serialization options. I want it to override every single serialization throughout my asp net core 2.0 project, but action return value that is not correct, I think this global property is not working in core 2.0

I have it written inside Configure exactly before app.UseMvc();

JsonConvert.DefaultSettings = () => new JsonSerializerSettings
            {
                Formatting = Formatting.Indented,
                TypeNameHandling = TypeNameHandling.Objects,
                ContractResolver = new CamelCasePropertyNamesContractResolver(),
                Converters = new List<JsonConverter> { new StringEnumConverter() }
            };

回答1:

In ASP.NET Core, this is configured when wiring up the services on the application in Startup.ConfigureServices. There is an fluent AddJsonOptions(Action<MvcJsonOptions>) extension to the IMvcBuilder returned by the AddMvc() extension. MvcJsonOptions exposes a SerializerSettings property which you can configure in your action code.

So instead of configuring once before registering MVC, it's done as part of the MVC registration.

Example incorporating your setup:

services.AddMvc()
  .AddJsonOptions( options =>
  {
    options.SerializerSettings.Formatting = Formatting.Indented;
    options.SerializerSettings.TypeNameHandling = TypeNameHandling.Objects;
    options.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
    options.SerializerSettings.Converters.Add(new StringEnumConverter());
  });

来源：https://stackoverflow.com/questions/46360651/setting-jsonconvert-defaultsettings-asp-net-core-2-0-not-working-as-expected