netcore---Program.cs配置相关信息，及读取配置信息

 代码：

using Autofac;
using Autofac.Extensions.DependencyInjection;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Serilog;
using System.Reflection;
using Yanwen.PLM.Entity;

namespace Yanwen.PLM.Worker
{
    public class Program
    {
        private static IConfiguration Configuration { get; set; }

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

        public static IHostBuilder CreateHostBuilder(string[] args)
          => Host.CreateDefaultBuilder(args)
            .UseServiceProviderFactory(new AutofacServiceProviderFactory())
            .ConfigureAppConfiguration((hostingContext, config) => {
                //var env = hostingContext.HostingEnvironment;
                //config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
                //      .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true, reloadOnChange: true);
                Configuration = config.Build();
            })
            .ConfigureServices(ConfigureServices)
            .ConfigureContainer<ContainerBuilder>(ConfigureContainer)
            .UseSerilog((ctx, config) => config.ReadFrom.Configuration(ctx.Configuration));

        private static void ConfigureServices(IServiceCollection services)
        {
            services.AddHostedService<Worker>();            
            services.AddScoped<DbContext, MySqlDbContext>();
            services.AddDbContext<MySqlDbContext>(options =>
            options.UseMySql(Configuration.GetConnectionString("Default")));

            var section = Configuration.GetSection("Redis:Default");
            string instanceName = section.GetSection("InstanceName").Value;
            string connectionString = section.GetSection("Connection").Value;
            int defaultDB = int.Parse(section.GetSection("DefaultDB").Value ?? "0");
            services.AddSingleton(new MyRedis(connectionString, instanceName, defaultDB));
        }

        private static void ConfigureContainer(ContainerBuilder containerBuilder)
        {
            // containerBuilder.RegisterType<EstimaterateService>().As<IEstimaterateService>();
            var dataAccess = Assembly.GetExecutingAssembly();
            containerBuilder.RegisterAssemblyTypes(dataAccess).Where(t => t.Name.EndsWith("Service")).AsImplementedInterfaces();
        }
    }
}