using Autofac;
using Autofac.Configuration;
using Microsoft.Extensions.Configuration;
namespace autofacConsole
{
    public static class AutofacExt
    {
        private static IContainer _container;
        public static void InitAutofac()
        {
            // Add the configuration to the ConfigurationBuilder.
            var config = new ConfigurationBuilder();
            config.AddJsonFile("autofac.json");
            // Register the ConfigurationModule with Autofac.
            var module = new ConfigurationModule(config.Build());
            var builder = new ContainerBuilder();
            builder.RegisterModule(module);
            // Set the dependency resolver to be Autofac.
            _container = builder.Build();
        }
        /// <summary>
        /// 从容器中获取对象
        /// </summary>
        /// <typeparam name="T"></typeparam>
        public static T GetFromFac<T>()
        {
            return _container.Resolve<T>();
            //   return (T)DependencyResolver.Current.GetService(typeof(T));
        }
        public static T GetFromFac<T>(string name)
        {
            return _container.ResolveNamed<T>(name);
        }
    }
}

public interface IOutput
    {
        void Write(string content);
    }
public class ConsoleOutput : IOutput
    {
        public void Write(string content)
        {
            Console.WriteLine(content);
        }
    }
class Program
    {        
        static void Main(string[] args)
        {
           AutofacExt.InitAutofac();
            var writer =AutofacExt.GetFromFac<IOutput>();
            writer.WriteDate();
            Console.ReadKey();
        }
    }    

{
  "defaultAssembly": "autofacConsole",
  "components": [
    {
      "type": "autofacConsole.ConsoleOutput, autofacConsole",
      "services": [
        {
          "type": "autofacConsole.IOutput,autofacConsole"
        }
      ],
      "instanceScope": "single-instance",
      "injectProperties": true
    }
  ]
}