1.首先需要安装 Autofac 和Autofac.Integration.Mvc
install-package Autofac -version5.2.0
install-package Autofac.Integration.Mvc -version 5.0.0
2.编写依赖注入和解析器类,并在该类中增加静态方法,实现注入和依赖解析,通过
System.Web.Mvc.DependencyResolver.SetResolver(new AutofacDependencyResolver(container));
来把当前的依赖注入加入到mvc框架中。
说明:
- DependencyResolver 是System.Web.Mvc 命名空间中的类,其方法SetResolver()接收一个IDependencyResolver接口类型的参数;
- AutofacDependencyResolver 是Autofac.Integration.Mvc命名空间中的类,该类实现了IDependencyResolver方法,在该类中只是把IDependencyResolver接口的两个方法GetService()和GetServices()作为虚拟方法,并未真正实现。该类是通过多个重载的构造函数来实现其生命周期的控制,并且至少接收一个ILifetimeScope类型注入容器参数来实现依赖项的解析。
3.为了使依赖解析器能够在系统启动时启动,需要在Global.asax.cs 中调用依赖解析器类中的静态方法进行初始化。
4. 控制器抽象,重建一个控制器基类,并在其中增加以来注入对象获取的方法,根据传入的接口类型自动匹配注入的依赖,从而得到该接口的实例。其他控制器通过继承该类而共享该类方法来获取依赖解析对象。
示例正代码:
1.仓储接口
using autofacdemo2.Models;
using System.Collections.Generic;
namespace autofacdemo2.Repository
{
public interface IStudentRepository
{
List<Student> GetStudents();
}
}
2.仓储实现
using autofacdemo2.Models;
using System.Collections.Generic;
namespace autofacdemo2.Repository
{
public class StudentRepository : IStudentRepository
{
private List<Student> students;
public StudentRepository()
{
students = new List<Student> {
new Student{ Id=1,Name="张三",Sex="男",Grade="二(一)班" },
new Student{ Id=2,Name="李四",Sex="女",Grade="二(二)班" },
new Student{ Id=3,Name="王五",Sex="男",Grade="二(一)班" }
};
}
public List<Student> GetStudents()
{
return students;
}
}
}
3.依赖解析类
using Autofac;
using Autofac.Integration.Mvc;
using autofacdemo2.Repository;
using System.Web.Mvc;
namespace autofacdemo2.App_Start
{
public class DependencyInject
{
private static IContainer _container;
public static IContainer Container {
get { return _container; }
}
/// <summary>
/// 注册相关接口
/// </summary>
public static void Initialise()
{
var builder = new ContainerBuilder();
builder.RegisterType<StudentRepository>().As<IStudentRepository>();
_container = builder.Build();
DependencyResolver.SetResolver(new AutofacDependencyResolver(_container));
}
}
}
4.控制器
using autofacdemo2.Repository;
using System.Linq;
using System.Web.Mvc;
namespace autofacdemo2.Controllers
{
public class HomeController : Controller
{
protected internal IStudentRepository GetStudentRepository()
{
return DependencyResolver.Current.GetService<IStudentRepository>();
}
// GET: Home
public ActionResult Index()
{
var students = GetStudentRepository();
ViewBag.Count = students.GetStudents().Count();
return View(students.GetStudents());
}
}
}
5.控制器基类
using System.Web.Mvc;
namespace autofacdemo2.Controllers
{
public class BasicController : Controller
{
// GET: Basic
protected internal TService GetService<TService>()
{
return DependencyResolver.Current.GetService<TService>();
}
}
}
6.控制器派生类
using autofacdemo2.Repository;
using System.Linq;
using System.Web.Mvc;
namespace autofacdemo2.Controllers
{
public class AutofacTestController : BasicController
{
// GET: AutofacTest
public ActionResult Index()
{
var studentrepository = GetService<IStudentRepository>();
ViewBag.Count = studentrepository.GetStudents().Count();
return View();
}
}
}