ASP.NET Core中使用Autofac进行属性注入

一些无关紧要的废话:

  作为一名双修程序员(自封的),喜欢那种使用Spring的注解形式进行依赖注入或者Unity的特性形式进行依赖注入,当然,形式大同小异,但结果都是一样的,通过属性进行依赖注入。

  ASP.NET Core中使用了自带的Dependency Injection作为了默认的IOC容器,当然有先天的优势,很多还是喜欢切换到Autofac作为IOC容器,Unity在.Net Core中还是有很大的优势的,但据我所知,Unity5已经由微软转交到基金会了,而且本身文档很少,翻译文档以及研究的就更加少了。

  当然,说了一堆废话,Autofac本身也是支持属性注入的,但是很多还是使用构造器进行注入,我本身也是推荐使用构造器进行注入(其实我不是这么想的),因为使用属性进行注入,将会暴露当前类的属性(Autofac属性注入属性必须为public),Spring可以用private进行注入的,但是不知道为什么,Autofac我使用private的时候注入进来的时候是null,如果文章有错误的话,希望高手能在留言处指出,帮助我及更多人进步。谢谢。

⒈新建一个ASP.NET Core MVC程序。

⒉添加 NuGet 包

Install-Package Autofac
Install-Package Autofac.Extensions.DependencyInjection

⒊新建实体类,服务抽象,服务实现。(DAL我这里就省略了,自行脑部)

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Threading.Tasks;
 5 
 6 namespace DapperDemo.Models
 7 {
 8     public class User
 9     {
10         public int id { get; set; }
11         public string username { get; set; }
12         public string password { get; set; }
13         public int enabled { get; set; }
14     }
15 }

 

 1 using DapperDemo.Models;
 2 using System;
 3 using System.Collections.Generic;
 4 using System.Linq;
 5 using System.Threading.Tasks;
 6 
 7 namespace DapperDemo.Services
 8 {
 9     public interface IUserService
10     {
11         IList<User> GetUsers();
12     }
13 }

 

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Threading.Tasks;
 5 using DapperDemo.Models;
 6 
 7 namespace DapperDemo.Services.Impl
 8 {
 9     public class UserService : IUserService
10     {
11         public IList<User> GetUsers()
12         {
13             return new List<User>
14             {
15                 new User
16                 {
17                     id = 1,
18                     username = "fanqi",
19                     password = "admin",
20                     enabled = 1
21                 }
22             };
23         }
24     }
25 }

⒋新建一个Aufofac Module,配置注入

 1 using Autofac;
 2 using DapperDemo.Services;
 3 using DapperDemo.Services.Impl;
 4 using Microsoft.AspNetCore.Mvc;
 5 using System;
 6 using System.Collections.Generic;
 7 using System.Linq;
 8 using System.Reflection;
 9 using System.Threading.Tasks;
10 
11 namespace DapperDemo.Module
12 {
13     public class DefaultModule : Autofac.Module
14     {
15         protected override void Load(ContainerBuilder builder)
16         {
17 
18             builder.RegisterType<UserService>().As<IUserService>().PropertiesAutowired()
19                 .InstancePerLifetimeScope();
20 
21             var controllersTypesInAssembly = typeof(Startup).Assembly.GetExportedTypes()
22                 .Where(type => typeof(ControllerBase).IsAssignableFrom(type)).ToArray();
23             builder.RegisterTypes(controllersTypesInAssembly).PropertiesAutowired();
24 
25         }
26     }
27 }

⒌修改Startup,替换IOC,使用Autofac作为默认的IOC容器

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Reflection;
 5 using System.Threading.Tasks;
 6 using Autofac;
 7 using Autofac.Extensions.DependencyInjection;
 8 using DapperDemo.Module;
 9 using Microsoft.AspNetCore.Builder;
10 using Microsoft.AspNetCore.Hosting;
11 using Microsoft.AspNetCore.Mvc;
12 using Microsoft.Extensions.Configuration;
13 using Microsoft.Extensions.DependencyInjection;
14 
15 namespace DapperDemo
16 {
17     public class Startup
18     {
19         public Startup(IConfiguration configuration)
20         {
21             Configuration = configuration;
22         }
23 
24         public IConfiguration Configuration { get; }
25 
26         // This method gets called by the runtime. Use this method to add services to the container.
27         public IServiceProvider ConfigureServices(IServiceCollection services)
28         {
29             services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2).AddControllersAsServices();
30             
31             // 添加 Autofac
32             var containerBuilder = new ContainerBuilder();
33 
34             containerBuilder.Populate(services);
35 
36             containerBuilder.RegisterModule<DefaultModule>();
37 
38             var container = containerBuilder.Build();
39 
40             return new AutofacServiceProvider(container);
41         }
42 
43         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
44         public void Configure(IApplicationBuilder app, IHostingEnvironment env)
45         {
46             if (env.IsDevelopment())
47             {
48                 app.UseDeveloperExceptionPage();
49             }
50             else
51             {
52                 app.UseExceptionHandler("/Home/Error");
53             }
54 
55             app.UseStaticFiles();
56             app.UseCookiePolicy();
57 
58             app.UseMvc(routes =>
59             {
60                 routes.MapRoute(
61                     name: "default",
62                     template: "{controller=Home}/{action=Index}/{id?}");
63             });
64         }
65     }
66 }

⒍新建控制器,在属性中注入服务抽象实现。

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Threading.Tasks;
 5 using DapperDemo.Models;
 6 using DapperDemo.Services;
 7 using Microsoft.AspNetCore.Http;
 8 using Microsoft.AspNetCore.Mvc;
 9 
10 namespace DapperDemo.Controllers
11 {
12     [Route("api/[controller]")]
13     [ApiController]
14     public class UserController : ControllerBase
15     {
16         public IUserService UserService { protected get; set; }
17 
18         [Route("get")]
19         public IList<User> GetUsers()
20         {
21             return UserService.GetUsers();
22         }
23 
24     }
25 }

⒎测试

ASP.NET Core中使用Autofac进行属性注入

 

上一篇:c# – 是Autofac IComponentContext.Resolve服务定位器模式


下一篇:c# – 如何使用Autofac来解析Nancy创建的子生命周期范围中的类型的每个请求依赖关系的实例