.net core 控制台程序使用依赖注入（Autofac）

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;
         }
     }
 }