1、Autofac IOC 容器 ，便于在其他类获取注入的对象

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using Autofac;
using Autofac.Core;
using Autofac.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection;
 
namespace BackToCOS.IoC
{
    /// <summary>
    /// Autofac IOC 容器
    /// </summary>
    public class AutofacContainer
    {
        private static ContainerBuilder _builder = new ContainerBuilder();
        private static IContainer _container;
        private static string[] _otherAssembly;
        private static List<Type> _types = new List<Type>();
        private static Dictionary<Type, Type> _dicTypes = new Dictionary<Type, Type>();
 
        /// <summary>
        /// 注册程序集
        /// </summary>
        /// <param name="assemblies">程序集名称的集合</param>
        public static void Register(params string[] assemblies)
        {
            _otherAssembly = assemblies;
        }
 
        /// <summary>
        /// 注册类型
        /// </summary>
        /// <param name="types"></param>
        public static void Register(params Type[] types)
        {
            _types.AddRange(types.ToList());
        }
        /// <summary>
        /// 注册程序集。
        /// </summary>
        /// <param name="implementationAssemblyName"></param>
        /// <param name="interfaceAssemblyName"></param>
        public static void Register(string implementationAssemblyName, string interfaceAssemblyName)
        {
            var implementationAssembly = Assembly.Load(implementationAssemblyName);
            var interfaceAssembly = Assembly.Load(interfaceAssemblyName);
            var implementationTypes =
                implementationAssembly.DefinedTypes.Where(t =>
                    t.IsClass && !t.IsAbstract && !t.IsGenericType && !t.IsNested);
            foreach (var type in implementationTypes)
            {
                var interfaceTypeName = interfaceAssemblyName + ".I" + type.Name;
                var interfaceType = interfaceAssembly.GetType(interfaceTypeName);
                if (interfaceType.IsAssignableFrom(type))
                {
                    _dicTypes.Add(interfaceType, type);
                }
            }
        }
        /// <summary>
        /// 注册
        /// </summary>
        /// <typeparam name="TInterface"></typeparam>
        /// <typeparam name="TImplementation"></typeparam>
        public static void Register<TInterface, TImplementation>() where TImplementation : TInterface
        {
            _dicTypes.Add(typeof(TInterface), typeof(TImplementation));
        }
 
        /// <summary>
        /// 注册一个单例实体
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="instance"></param>
        public static void Register<T>(T instance) where T:class
        {
            _builder.RegisterInstance(instance).SingleInstance();
        }
 
        /// <summary>
        /// 构建IOC容器
        /// </summary>
        public static IServiceProvider Build(IServiceCollection services)
        {
            if (_otherAssembly != null)
            {
                foreach (var item in _otherAssembly)
                {
                    _builder.RegisterAssemblyTypes(Assembly.Load(item));
                }
            }
 
            if (_types != null)
            {
                foreach (var type in _types)
                {
                    _builder.RegisterType(type);
                }
            }
 
            if (_dicTypes != null)
            {
                foreach (var dicType in _dicTypes)
                {
                    _builder.RegisterType(dicType.Value).As(dicType.Key);
                }
            }
 
            _builder.Populate(services);
            _container = _builder.Build();
            return new AutofacServiceProvider(_container);
        }
 
        /// <summary>
        ///
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <returns></returns>
        public static T Resolve<T>()
        {
            return _container.Resolve<T>();
        }
 
        public static T Resolve<T>(params Parameter[] parameters)
        {
            return _container.Resolve<T>(parameters);
        }
 
        public static object Resolve(Type targetType)
        {
            return _container.Resolve(targetType);
        }
 
        public static object Resolve(Type targetType, params Parameter[] parameters)
        {
            return _container.Resolve(targetType, parameters);
        }
    }
}

2、用nuget安装

       using Microsoft.Extensions.Configuration;
       using Microsoft.Extensions.DependencyInjection;

3、Program类如下

using BackToCOS.IoC;
using log4net;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Myvas.AspNetCore.TencentCos;
using System;
using System.IO;
using Topshelf;

namespace BackToCOS
{
    class Program
    {
        static void Main(string[] args)
        {
            var configuration = new ConfigurationBuilder()
              .SetBasePath(Directory.GetCurrentDirectory())
              .AddJsonFile("appsettings.json", true, true)
              .AddJsonFile("appsettings.Development.json", true, true)
              .Build();
            IServiceCollection services = new ServiceCollection();

            services.AddTencentCos(options =>
            {
                options.SecretId = configuration["TencentCos:SecretId"];
                options.SecretKey = configuration["TencentCos:SecretKey"];
            });
            services.AddLogging(builder => builder
               .AddConfiguration(configuration.GetSection("Logging"))
               .AddConsole());
            //注入
            services.AddSingleton<ITencentCosHandler, TencentCosHandler>();
            //用Autofac接管
            AutofacContainer.Build(services);
            log4net.Config.XmlConfigurator.ConfigureAndWatch(LogManager.CreateRepository("NETCoreRepository"), new FileInfo(AppDomain.CurrentDomain.BaseDirectory + "log4net.config"));
            HostFactory.Run(x =>
            {
                x.UseLog4Net();
                x.Service<BackupServiceRunner>();
                x.RunAsLocalSystem();
                x.SetDescription("备份到cos的服务");
                x.SetDisplayName("备份到cos的服务");
                x.SetServiceName("BackToCOS");
                x.EnablePauseAndContinue();
            });
        }
    }

}

4、用容器获取事例（非构造函数）

using log4net;
using Microsoft.Extensions.Options;
using Myvas.AspNetCore.TencentCos;
using Quartz;
using System;
using System.Collections.Generic;
using System.Text;
using System.Threading.Tasks;

namespace BackToCOS.Jobs
{
    //DisallowConcurrentExecution属性标记任务不可并行
    [DisallowConcurrentExecution]
    public class BackupJob : IJob
    {
        private readonly ILog _log = LogManager.GetLogger("NETCoreRepository", typeof(BackupJob));
        public Task Execute(IJobExecutionContext context)
        {
            try
            {
                _log.Info("测试任务,当前系统时间:" + DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));
                ITencentCosHandler tencentCosHandler = IoC.AutofacContainer.Resolve<ITencentCosHandler>();
                var ss = tencentCosHandler.AllBucketsAsync();
                return Task.CompletedTask;
            }
            catch (Exception ex)
            {
                JobExecutionException e2 = new JobExecutionException(ex);
                _log.Error("测试任务异常", ex);
            }
            return Task.CompletedTask;
        }
    }
}

Autofac-.net core控制台使用依赖注入【转】