如何将启动类添加到.net核心3中的worker服务模板

dotnet new worker -n MyWorkerService

cd MyWorkerService

<PackageReference Include="Microsoft.Extensions.Hosting" Version="3.1.0" />

using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using System;
using System.Threading;
using System.Threading.Tasks;

namespace MyWorkerService
{
    public class Worker : IHostedService, IDisposable
    {
        private readonly ILogger<Worker> _logger;
        private Timer _timer;

        public Worker(ILogger<Worker> logger)
        {
            _logger = logger;
        }

        public Task StartAsync(CancellationToken cancellationToken)
        {
            _logger.LogInformation("Worker started at: {time}", DateTimeOffset.Now);

            _timer = new Timer(DoWork, null, TimeSpan.Zero, TimeSpan.FromSeconds(5));

            return Task.CompletedTask;
        }

        private void DoWork(object state)
        {
            _logger.LogInformation("Worker is working at: {time}", DateTimeOffset.Now);
        }

        public Task StopAsync(CancellationToken cancellationToken)
        {
            _logger.LogInformation("Worker stopped at: {time}", DateTimeOffset.Now);

            _timer?.Change(Timeout.Infinite, 0);

            return Task.CompletedTask;
        }

        public void Dispose()
        {
            _timer?.Dispose();
        }
    }
}

using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;

namespace MyWorkerService
{
    public class Program
    {
        public static void Main(string[] args)
        {
            CreateHostBuilder(args).Build().Run();
        }

        public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureServices((hostContext, services) =>
                {
                    services.AddHostedService<Worker>();
                });
    }
}

dotnet run