.Net Core 3.0 JsonSerializer populate existing object

Question

I\'m preparing a migration from ASP.NET Core 2.2 to 3.0.

As I don\'t use more advanced JSON features (but maybe one as described below), and 3.0 now comes with a buil

Answer 1

If you already use AutoMapper in your project or don't mind having dependency on it, you can merge objects in a following way:

var configuration = new MapperConfiguration(cfg => cfg
    .CreateMap<Model, Model>()
    .ForAllMembers(opts => opts.Condition((src, dest, srcMember) => srcMember != default)));
var mapper = configuration.CreateMapper();

var destination = new Model {Title = "Startpage", Link = "/index"};
var source = new Model {Head = "Latest news", Link = "/news"};

mapper.Map(source, destination);

class Model
{
    public string Head { get; set; }
    public string Title { get; set; }
    public string Link { get; set; }
}