Hands-On RESTful Web Services with ASP.NET Core 3

The Program.cs and Startup.cs files

Let's continue by examining the Program.cs file of a web API project:

using System;using System.Collections.Generic;using System.Linq;using System.Threading.Tasks;using Microsoft.AspNetCore.Hosting;using Microsoft.Extensions.Configuration;using Microsoft.Extensions.Hosting;using Microsoft.Extensions.Logging;namespace SampleAPI{    public class Program    {        public static void Main(string[] args)        {            CreateHostBuilder(args).Build().Run();        }        public static IHostBuilder CreateHostBuilder(string[]         args) =>            Host.CreateDefaultBuilder(args)                .ConfigureWebHostDefaults(webBuilder =>                {                    webBuilder.UseStartup<Startup>();                });    }}

The preceding code imports the Microsoft.AspNetCore.Hosting and Microsoft.Extensions.Hosting namespaces. ...