傻瓜式使用AutoFac

定义一个接口：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace AutoFacTest
{
    public interface IAddressService
    {
        string GetAddress(int contactNumber);
    }
}

实现类：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace AutoFacTest
{
    public class AddressService : IAddressService
    {
        public string GetAddress(int contactNumber)
        {
            string result = string.Empty;

            if (contactNumber == 123)
                result = "上海浦东";

            return result;
        }
    }
}

先来定义一个容器：

using Autofac;
using Autofac.Core;
using Autofac.Integration.Mvc;
using Autofac.Extras.AggregateService;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace AutoFacTest.Common
{
    public class ObjectContainer
    {
        public static IContainer Container
        {
            get
            {
                return _container;
            }
        }

        private static IContainer _container;

        private ObjectContainer()
        {
        }

        public static void Initialize(Action<ContainerBuilder> action)
        {
            var builder = new ContainerBuilder();

            if (action != null)
            {
                action(builder);
            }

            _container = builder.Build();
        }

        public static bool IsRegistered<TService>()
        {
            ThrowIfNotInitialized();
            return _container.IsRegistered<TService>();
        }

        public static bool IsRegistered(Type serviceType)
        {
            ThrowIfNotInitialized();
            return _container.IsRegistered(serviceType);
        }

        public static TService Resolve<TService>(params Parameter[] parameters)
        {
            ThrowIfNotInitialized();
            return _container.Resolve<TService>(parameters);
        }

        public static object Resolve(Type serviceType, params Parameter[] parameters)
        {
            ThrowIfNotInitialized();
            return _container.Resolve(serviceType, parameters);
        }

        public static TService ResolveNamed<TService>(string serviceName, params Parameter[] parameters)
        {
            ThrowIfNotInitialized();
            return _container.ResolveNamed<TService>(serviceName, parameters);
        }

        public static object ResolveNamed(string serviceName, Type serviceType, params Parameter[] parameters)
        {
            ThrowIfNotInitialized();
            return _container.ResolveNamed(serviceName, serviceType, parameters);
        }

        public static bool TryResolve<TService>(out TService service)
        {
            ThrowIfNotInitialized();
            return _container.TryResolve<TService>(out service);
        }

        public static bool TryResolve(Type serviceType, out object service)
        {
            ThrowIfNotInitialized();
            return _container.TryResolve(serviceType, out service);
        }

        private static void ThrowIfNotInitialized()
        {
            if (_container == null)
                throw new InvalidOperationException("Container should be initialized before using it.");
        }
    }
}

Global中注册AddressService和IAddressService的依赖关系，自动将实现类AddressService注入到Ioc容器中。

using AutoFacTest.Common;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Optimization;
using System.Web.Routing;
using System.Web.Security;
using System.Web.SessionState;
using Autofac;
using Autofac.Integration.Mvc;
using Autofac.Extras.AggregateService;

namespace AutoFacTest
{
    public class Global : HttpApplication
    {
        private System.ComponentModel.IContainer components = null;
        protected void Application_Start(object sender, EventArgs e)
        {
            // Code that runs on application startup
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
            RegisterDependencies();
        }

        private void RegisterDependencies()
        {
            ObjectContainer.Initialize(builder =>
            {
                builder.RegisterType<AddressService>().As<IAddressService>().InstancePerDependency();
            });
        }
    }
}

使用：

 IAddressService svc = Common.ObjectContainer.Resolve<IAddressService>();
            string address = svc.GetAddress(123);

再也不用手动new那么多 object。再也不用手写factory，AutoFac就是这么方便。