WebApiForAvaloniaProj/WebApplicationAvaloniaForMe/Program.cs

using WebApplicationAvaloniaForMe.Models;
using Microsoft.EntityFrameworkCore;
using Newtonsoft.Json;

var builder = WebApplication.CreateBuilder(args);
// Add services to the container.
builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
builder.Services.AddDbContext<KuzminivpostgrContext>();

var app = builder.Build();
app.MapGet("/", () => "Hello, world");

app.MapGet("/number", () => "chto to tipo takogo: 100500");

app.MapGet("/characterlist", (KuzminivpostgrContext db) => JsonConvert.SerializeObject(db.Mycharacters.Include(x=>x.Properties).ToList(), Formatting.Indented, new JsonSerializerSettings { ReferenceLoopHandling = ReferenceLoopHandling.Ignore }));

app.MapGet("/character/{id:int}",
    (KuzminivpostgrContext db, int id) =>
    JsonConvert.SerializeObject(db.Mycharacters.Include(x => x.GenderNavigation).Include(x => x.Properties).FirstOrDefault(x => x.Id == id),
    Formatting.Indented, new JsonSerializerSettings { ReferenceLoopHandling = ReferenceLoopHandling.Ignore }));

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();

app.UseAuthorization();

app.MapControllers();

app.Run();