ASP.NET Core必備知識之Autofac

使用Autofac替換掉微軟的DI

本文的項目為ASP.NET Core3.1，傳統三層架構 在這就不過多介紹Autofac，直接上代碼

Autofac官網：https://autofac.org/

Program.cs的 IHostBuilder 方法內加上 .UseServiceProviderFactory(new AutofacServiceProviderFactory())（如下圖）

    public static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)
             .UseServiceProviderFactory(new AutofacServiceProviderFactory())//啟用autofac容器
            .ConfigureWebHostDefaults(webBuilder =>
            {
              webBuilder.UseStartup<Startup>();
            });
  }

在Startup.cs內新增 ConfigureContainer 方法
屬性介紹
RegisterAssemblyTypes：寄存器程序集類型
AsImplementedInterfaces：實現的接口
InstancePerDependency：實例依賴關系
PropertiesAutowired：屬性自動連接

        /// <summary>
        /// 配置Autofac容器替換微軟的DI
        /// </summary>
        /// <param name="builder"></param>
        public void ConfigureContainer(ContainerBuilder builder)
        {
            var basePath = AppContext.BaseDirectory;
            //DALService所在程序集命名空間
            string DALPath = Path.Combine(basePath, "GraduationProject.DAL.dll");
            Assembly DAL = Assembly.LoadFrom(DALPath);
            //BLLService所在程序集命名空間
            string BLLPath = Path.Combine(basePath, "GraduationProject.BLL.dll");
            Assembly BLL = Assembly.LoadFrom(BLLPath);

            builder.RegisterAssemblyTypes(DAL).InstancePerDependency().PropertiesAutowired();
            builder.RegisterAssemblyTypes(BLL).AsImplementedInterfaces().InstancePerDependency().PropertiesAutowired();
        }