builder.Host.UseServiceProviderFactory(new AutofacServiceProviderFactory()); builder.Host.ConfigureContainer<ContainerBuilder>(containerBuilder => { //堆代码 duidaima.com //在这里写注入代码 });二、构造函数注入
public interface IUserService { public string GetUserName(); } public class UserService:IUserService { public string GetUserName() { return "张三"; } }在上面的ConfigureContainer方法把UserService注入进来,默认是瞬时注入
public class HomeController : Controller { // 堆代码 duidaima.com [AutowiredProperty] private IUserService userService { get; set; } public IActionResult Index() { string name = userService.GetUserName(); return View(); } }2.新增自定义特性类AutowiredPropertyAttribute.cs
[AttributeUsage(AttributeTargets.Property)]//为了支持属性注入,只能打到属性上 public class AutowiredPropertyAttribute: Attribute { }3.增加识别特性类AutowiredPropertySelector.cs
public class AutowiredPropertySelector : IPropertySelector { public bool InjectProperty(PropertyInfo propertyInfo, object instance) { //判断属性的特性是否包含自定义的属性,标记有返回true return propertyInfo.CustomAttributes.Any(s => s.AttributeType == typeof(AutowiredPropertyAttribute)); } }4.因为Controller 默认是由 Mvc 模块管理的,需要把控制器放到IOC容器中,在Program.cs中增加
//让控制器实例由容器创建 builder.Services.Replace(ServiceDescriptor.Transient<IControllerActivator, ServiceBasedControllerActivator>());5.把容器注册到IOC容器,在Program.cs的ConfigureContainer()增加
//获取所有控制器类型并使用属性注入 Type[] controllersTypeAssembly = typeof(Program).Assembly.GetExportedTypes() .Where(type => typeof(ControllerBase).IsAssignableFrom(type)).ToArray(); containerBuilder.RegisterTypes(controllersTypeAssembly).PropertiesAutowired(new AutowiredPropertySelector());
验证:
/// <summary> /// 瞬时注入 /// </summary> public interface ITransitDenpendency { } /// <summary> /// 单例注入标识 /// </summary> public interface ISingletonDenpendency { } /// <summary> /// 生命周期注入标识 /// </summary> public interface IScopeDenpendency { }2.把上面要注入的类实现上面的接口
/// <summary> /// Ioc管理 /// </summary> public static class IocManager { /// <summary> /// 批量注入扩展 /// </summary> /// <param name="builder"></param> /// <param name="assembly"></param> public static void BatchAutowired(this ContainerBuilder builder, Assembly assembly) { var transientType = typeof(ITransitDenpendency); //瞬时注入 var singletonType = typeof(ISingletonDenpendency); //单例注入 var scopeType = typeof(IScopeDenpendency); //单例注入 //瞬时注入 builder.RegisterAssemblyTypes(assembly).Where(t => t.IsClass && !t.IsAbstract && t.GetInterfaces().Contains(transientType)) .AsSelf() .AsImplementedInterfaces() .InstancePerDependency() .PropertiesAutowired(new AutowiredPropertySelector()); //单例注入 builder.RegisterAssemblyTypes(assembly).Where(t => t.IsClass && !t.IsAbstract && t.GetInterfaces().Contains(singletonType)) .AsSelf() .AsImplementedInterfaces() .SingleInstance() .PropertiesAutowired(new AutowiredPropertySelector()); //生命周期注入 builder.RegisterAssemblyTypes(assembly).Where(t => t.IsClass && !t.IsAbstract && t.GetInterfaces().Contains(scopeType)) .AsSelf() .AsImplementedInterfaces() .InstancePerLifetimeScope() .PropertiesAutowired(new AutowiredPropertySelector()); }4.把注入类ConfigureContainer改成
public class AutofacRegisterModule : Autofac.Module { protected override void Load(ContainerBuilder builder) { //获取所有控制器类型并使用属性注入 Type[] controllersTypeAssembly = typeof(Program).Assembly.GetExportedTypes() .Where(type => typeof(ControllerBase).IsAssignableFrom(type)).ToArray(); builder.RegisterTypes(controllersTypeAssembly).PropertiesAutowired(new AutowiredPropertySelector()); //批量自动注入,把需要注入层的程序集传参数,注入Service层的类 builder.BatchAutowired(typeof(UserService).Assembly); //注入其它层的containerBuilder.BatchAutowired(typeof(其它层的任务一个类).Assembly); } }
ConfigureContainer的代码变成
五、手动获取实例
private static object obj = new object(); private static ILifetimeScope _container { get; set; } public static void InitContainer(ILifetimeScope container) { //防止过程中方法被调用_container发生改变 if (_container == null) { lock (obj) { if (_container == null) { _container = container; } } } } /// <summary> /// 手动获取实例 /// </summary> /// <typeparam name="T"></typeparam> /// <returns></returns> public static T Resolve<T>() { return _container.Resolve<T>(); }2.在Program.cs中增加
public class DataHelper { //手动注入UserService private static IUserService userService = IocManager.Resolve<IUserService>(); public static string GetData() { return userService.GetUserName(); } }成功获取到值,证明从容器中获取成功。
public class UserService :ITransitDenpendency { public string GetUserName() { return "张三"; } }
2.一接口多实现
public class UserService :IUserService { public string GetUserName() { return "张三"; } } public class UserService2 : IUserService { public string GetUserName() { return "张三2号"; } }