Autofac详解
零、文章目录
一、Autofac详解
1、概述
- Autofac是第三方IOC容器,是当前最流行的IOC容器。
- 功能强大,比asp.netcore内置容器强大得多,支持属性注入和方法注入,支持AOP。
- 官网地址:http://autofac.org/
- 源码下载地址:https://github.com/autofac/Autofac
2、快速开始
(1)Nuget引入程序包
Autofac 基于版本6.3演示,Net5
(2)容器创建对象
//创建一个容器建造者 ContainerBuilder containerBuilder = new ContainerBuilder(); //注册普通类 containerBuilder.RegisterType
(); //build一下,得到一个容器 IContainer container = containerBuilder.Build(); //可以基于容器来获取对象的实例 Honer phone = container.Resolve
();
3、注册的类型
(1)注册普通类
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
(); IContainer container = containerBuilder.Build(); Honer phone = container.Resolve
();
(2)注册抽象与实现
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
(); IContainer container = containerBuilder.Build(); IPhone phone = container.Resolve
();
(3)注册程序集
- RegisterAssemblyTypes(程序集数组),程序集必须是public的
- AsImplementedInterfaces():表示注册的类型,以接口的方式注册
- PropertiesAutowired():支持属性注入
- Where:满足条件类型注册
var basePath = AppContext.BaseDirectory; var dll = Path.Combine(basePath, "MyAutofac.dll"); ContainerBuilder containerBuilder = new ContainerBuilder(); var assemblysServices = Assembly.LoadFrom(dll); containerBuilder.RegisterAssemblyTypes(assemblysServices) .Where(t => !t.Name.EndsWith("XXX")) .AsImplementedInterfaces() .PropertiesAutowired(); IContainer container = containerBuilder.Build(); ITeacher teacher = container.Resolve
();

4、三种注入方式
(1)构造函数注入
默认支持,无法用特性进行筛选,默认选参数最多的构造函数进行注入
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
(); containerBuilder.RegisterType
().As
(); containerBuilder.RegisterType
().As
(); IContainer container = containerBuilder.Build(); ITeacher teacher = container.Resolve
();

(2)全部属性注入
关键词
PropertiesAutowired,这个对象所有属性全部注入
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
(); containerBuilder.RegisterType
().As
().PropertiesAutowired(); containerBuilder.RegisterType
().As
(); IContainer container = containerBuilder.Build(); ITeacher teacher = container.Resolve
();

(3)标记特性的属性注入
关键词
PropertiesAutowired,定义特性选择器CustomPropertySelector
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
(); containerBuilder.RegisterType
().As
().PropertiesAutowired(new CustomPropertySelector()); containerBuilder.RegisterType
().As
(); IContainer container = containerBuilder.Build(); ITeacher teacher = container.Resolve
();
public class CustomPropertySelector : IPropertySelector { public bool InjectProperty(PropertyInfo propertyInfo, object instance) { var flag = propertyInfo.CustomAttributes.Any(it => it.AttributeType == typeof(SelectPropAttribute)); return flag; } }

(4)方法注入
关键词
OnActivated,指定调用方法
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
(); containerBuilder.RegisterType
().As
() .OnActivated(p => { p.Instance.SetStudent1(p.Context.Resolve
()); }); containerBuilder.RegisterType
().As
(); IContainer container = containerBuilder.Build(); ITeacher teacher = container.Resolve
();

5、对象生命周期
(1)瞬时生命周期
每次获取都是全新的实例,关键词
InstancePerDependency,默认的生命周期
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
().InstancePerDependency(); IContainer container = containerBuilder.Build(); IPhone phone1 = container.Resolve
(); IPhone phone2 = container.Resolve
(); bool isflg1 = object.ReferenceEquals(phone1, phone2); Console.WriteLine($"InstancePerDependency:phone1==phone2=>{isflg1}");
InstancePerDependency:phone1==phone2=>False
(2)单例生命周期
同一个进程内都是同一个实例,关键词
SingleInstance
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
().SingleInstance(); IContainer container = containerBuilder.Build(); IPhone phone1 = container.Resolve
(); IPhone phone2 = container.Resolve
(); bool isflg1 = object.ReferenceEquals(phone1, phone2); Console.WriteLine($"SingleInstance:phone1==phone2=>{isflg1}"); using (var scope = container.BeginLifetimeScope()) { IPhone phone3 = scope.Resolve
(); IPhone phone4 = scope.Resolve
(); bool isflg2 = object.ReferenceEquals(phone3, phone4); Console.WriteLine($"SingleInstance:phone3==phone4=>{isflg2}"); bool isflg3 = object.ReferenceEquals(phone1, phone3); Console.WriteLine($"SingleInstance:phone1==phone3=>{isflg3}"); }
SingleInstance:phone1==phone2=>True SingleInstance:phone3==phone4=>True SingleInstance:phone1==phone3=>True
(3)作用域生命周期
同一个作用域内都是同一个实例,关键词
InstancePerLifetimeScope
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
().InstancePerLifetimeScope(); IContainer container = containerBuilder.Build(); IPhone phone1 = container.Resolve
(); IPhone phone2 = container.Resolve
(); bool isflg1 = object.ReferenceEquals(phone1, phone2); Console.WriteLine($"InstancePerLifetimeScope:phone1==phone2=>{isflg1}"); IPhone phone3 = null; IPhone phone4 = null; using (var scope = container.BeginLifetimeScope()) { phone3 = scope.Resolve
(); phone4 = scope.Resolve
(); bool isflg2 = object.ReferenceEquals(phone3, phone4); Console.WriteLine($"InstancePerLifetimeScope:phone3==phone4=>{isflg2}"); bool isflg3 = object.ReferenceEquals(phone1, phone3); Console.WriteLine($"InstancePerLifetimeScope:phone1==phone3=>{isflg3}"); } IPhone phone5 = null; IPhone phone6 = null; using (var scope = container.BeginLifetimeScope()) { phone5 = scope.Resolve
(); phone6 = scope.Resolve
(); bool isflg2 = object.ReferenceEquals(phone5, phone6); Console.WriteLine($"InstancePerLifetimeScope:phone5==phone6=>{isflg2}"); bool isflg3 = object.ReferenceEquals(phone1, phone5); Console.WriteLine($"InstancePerLifetimeScope:phone1==phone5=>{isflg3}"); } bool isflg4 = object.ReferenceEquals(phone3, phone5); Console.WriteLine($"InstancePerLifetimeScope:phone3==phone5=>{isflg4}");
InstancePerLifetimeScope:phone1==phone2=>True InstancePerLifetimeScope:phone3==phone4=>True InstancePerLifetimeScope:phone1==phone3=>False InstancePerLifetimeScope:phone5==phone6=>True InstancePerLifetimeScope:phone1==phone5=>False InstancePerLifetimeScope:phone3==phone5=>False
(4)作用域范围生命周期
在作用域范围外无法创建实例,在作用域范围里面,同一个作用域下面的对象是同一个,关键词
InstancePerMatchingLifetimeScope
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
().InstancePerMatchingLifetimeScope("scope1", "scope2"); IContainer container = containerBuilder.Build(); IPhone phone1 = null; IPhone phone2 = null; using (var scope = container.BeginLifetimeScope("scope1")) { phone1 = scope.Resolve
(); phone2 = scope.Resolve
(); bool isflg1 = object.ReferenceEquals(phone1, phone2); Console.WriteLine($"InstancePerMatchingLifetimeScope:phone1==phone2=>{isflg1}"); } IPhone phone3 = null; using (var scope = container.BeginLifetimeScope("scope2")) { phone3 = scope.Resolve
(); } IPhone phone4 = null; using (var scope = container.BeginLifetimeScope("scope2")) { phone4 = scope.Resolve
(); } bool isflg2 = object.ReferenceEquals(phone3, phone4); Console.WriteLine($"InstancePerMatchingLifetimeScope:phone3==phone4=>{isflg2}"); bool isflg3 = object.ReferenceEquals(phone1, phone3); Console.WriteLine($"InstancePerMatchingLifetimeScope:phone1==phone3=>{isflg3}");
InstancePerMatchingLifetimeScope:phone1==phone2=>True InstancePerMatchingLifetimeScope:phone3==phone4=>False InstancePerMatchingLifetimeScope:phone1==phone3=>False
(5)一次请求同一个对象
关键词
InstancePerRequest,只能在web项目中调试,控制台报错
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
().InstancePerRequest(); IContainer container = containerBuilder.Build(); IPhone phone1 = container.Resolve
(); IPhone phone2 = container.Resolve
(); bool isflg1 = object.ReferenceEquals(phone1, phone2); Console.WriteLine($"InstancePerRequest:phone1==phone2=>{isflg1}");
6、支持配置文件注册
(1)nuget引入程序集
Autofac Autofac.Configuration Microsoft.Extensions.Configuration.Json
(2)配置文件autofac.json,属性->始终复制
{ "components": [ { //实现 "type": "Net5.IOC.Honer,Net5.IOC", //抽象 "services": [ { "type": "Net5.IOC.IPhone,Net5.IOC" } ], //生命周期 "instanceScope": "single-instance", //属性注入 "injectProperties": true } ] }
(3)通过配置文件注册创建对象
ContainerBuilder containerBuilder = new ContainerBuilder(); IConfigurationBuilder config = new ConfigurationBuilder(); IConfigurationSource autofacJsonConfigSource = new JsonConfigurationSource() { Path = "Autofac/autofac.json", Optional = false,//boolean,默认就是false,可不写 ReloadOnChange = true,//同上 }; config.Add(autofacJsonConfigSource); ConfigurationModule module = new ConfigurationModule(config.Build()); containerBuilder.RegisterModule(module); IContainer container = containerBuilder.Build(); IPhone phone1 = container.Resolve
(); IPhone phone2 = container.Resolve
(); bool isflg1 = object.ReferenceEquals(phone1, phone2); Console.WriteLine($"配置文件注册:phone1==phone2=>{isflg1}");
(4)运行结果
配置文件注册:phone1==phone2=>True
7、支持AOP切面编程
可以在不修改方法的前提下,在方法前后添加公共逻辑,日志,异常,缓存等
(1)nuget引入程序集
Castle.Core Autofac.Extras.DynamicProxy
(2)自定义一个切面类实现IInterceptor接口
public class CustomInterceptor : IInterceptor { public void Intercept(IInvocation invocation) { Console.WriteLine("方法执行前。。。"); //执行当前方法 invocation.Proceed(); Console.WriteLine("方法执行后。。。"); } }
(3)在抽象/实现类上添加特性标记
[Intercept(typeof(CustomInterceptor))] public interface IPhone { string ShowName(); } //实现类虚方法 public class Honer : IPhone { public virtual string ShowName() { Console.WriteLine("Honer"); return "Honer"; } }
(4)在容器中注册关系创建对象
- EnableInterfaceInterceptors + 特性标记在抽象上,所有实现类都支持AOP
- EnableInterfaceInterceptors + 特性标记到实现类上,标记的类就支持AOP
- EnableClassInterceptors,要支持AOP的方法必须要是用virtual虚方法
- EnableClassInterceptors + 特性标记在抽象上,所有实现类都支持AOP
- EnableClassInterceptors + 特性标记到实现类上,标记的类就支持AOP
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().As
().EnableInterfaceInterceptors(); containerBuilder.RegisterType(typeof(CustomInterceptor)); IContainer container = containerBuilder.Build(); IPhone phone = container.Resolve
(); phone.ShowName();
(5)运行结果
方法执行前。。。 Honer 方法执行后。。。
8、单抽象多实现问题
(1)在容器中注册关系创建对象
ContainerBuilder containerBuilder = new ContainerBuilder(); containerBuilder.RegisterType
().Named
("Honer"); containerBuilder.RegisterType
().Named
("Huawei"); IContainer container = containerBuilder.Build(); IPhone honer = container.ResolveNamed
("Honer"); IPhone huawei = container.ResolveNamed
("Huawei"); honer.ShowName(); huawei.ShowName();
(2)运行结果
Honer Huawei
9、集成到Asp.NetCore5框架
(1)nuget引入程序集
Autofac Autofac.Extensions.DependencyInjection
(2)定义实现类和抽象
public class UserService : IUserService { private IUserRepository UserRepositoryCtor { get; set; } public UserService(IUserRepository userRepository) { UserRepositoryCtor = userRepository; } public string Login(string username, string password) { return "登录成功"; } }
(3)添加控制器和页面
public class FourthController : Controller { private IUserService _userService; public FourthController(IUserService userService) { this._userService = userService; } public IActionResult Index() { object result = this._userService.Login("username", "password"); return View(result); } }
@model String this is fourth index...
@Model
(4)在Program替换容器工厂
public class Program { public static void Main(string[] args) { CreateHostBuilder(args).Build().Run(); } public static IHostBuilder CreateHostBuilder(string[] args) => Host.CreateDefaultBuilder(args) .ConfigureWebHostDefaults(webBuilder => { webBuilder.UseStartup
(); }) .UseServiceProviderFactory(new AutofacServiceProviderFactory()); }
(5)在Startup类的ConfigureServices方法中替换创建控制器的类
//控制器默认是有IControllerActivator创建的,替换成由容器创建 services.Replace(ServiceDescriptor.Transient
());
(6)注册抽象和实现的关系
在
Startup类中专门增加一个方法ConfigureContainer,用于注册抽象和实现,可以把这些注册信息进行模块化封装到AutofacModule当抽象类和实现非常多的时候,可以将整个dll注册,特殊的关系可以写在后面覆盖前面的注册关系。
/// /// Autofac专用:注册抽象和细节之间的关系,使用autofac后原来内置注册的关系要注释掉 /// Autofac和ServiceCollection是二者并存的,Autofac会接管ServiceCollection的一切 /// /// public void ConfigureContainer(ContainerBuilder builder) { builder.RegisterModule
(); }
public class AutofacModule : Module { /// /// 重写Autofac管道中的Load方法,在这里注入注册的内容 /// /// protected override void Load(ContainerBuilder builder) { //注册抽象与实现 builder.RegisterType
().As
(); builder.RegisterType
().As
(); //注册所有控制器类 var controllersTypesInAssembly = typeof(Startup).Assembly.GetExportedTypes() .Where(type => typeof(ControllerBase).IsAssignableFrom(type)).ToArray(); //实现属性注入,这边无法实现方法注入 builder.RegisterTypes(controllersTypesInAssembly).PropertiesAutowired(); } }
(7)运行结果


(8)在Startup的Configure方法中用容器创建对象
using (var container = host.Services.CreateScope()) { IUserService userService = container.ServiceProvider.GetService
(); }

(9)单抽象多实现集成到框架
注入的时候通过构造函数或者属性注入autofac上下文实例,再根据名称创建对应实例。
定义单抽象和多实例类
//抽象 public interface ITestService { string Show(); } //实现1 public class TestServiceA : ITestService { public string Show() { return "TestServiceA"; } } //实现2 public class TestServiceB : ITestService { public string Show() { return "TestServiceB"; } }
在
AutofacModule注册抽象和实现的关系
//单抽象多实现注册 builder.RegisterType
().Named
("a"); builder.RegisterType
().Named
("b");
添加控制器和页面
public class FifthController : Controller { private IComponentContext _componentContext; public FifthController(IComponentContext componentContext) { this._componentContext = componentContext; } public IActionResult Index() { ITestService testServiceA = _componentContext.ResolveNamed
("a"); ITestService testServiceB = _componentContext.ResolveNamed
("b"); object result = $"{testServiceA.Show()}--{testServiceB.Show()}"; return View(result); } }
@model String this is Fifth index...
@Model
运行结果

发布者:全栈程序员-站长,转载请注明出处:https://javaforall.net/207281.html原文链接:https://javaforall.net
