解决条件依赖关系autofac
问题描述:
我想解决基于条件的依赖关系。解决条件依赖关系autofac
private static readonly Dictionary<string, Action<ContainerBuilder>> QRTypeDictionary =
new Dictionary<string, System.Action<ContainerBuilder>>() {
{ "REST" , (builder)=> builder
.RegisterType<RestPublisher>()
.As<Publisher>()},
{ "DB" , (builder)=> builder
.RegisterType<DBPublisher>()
.As<Publisher>()}
}
我只是想确定如果这是解决依赖条件的唯一方法。我一直在使用Ninject到目前为止并正在寻找类似如下:
kernel.Bind<Publisher>()
.To<DbPublisher>()
.When(x => Defs.AppSettings.PublisherType == "DB")
只是想确认我在做正确的事与Autofac
答
我可以看到3个解决方案,以实现你想要的。
-
使用Lambda
builder.RegisterType<DbPublisher>().AsSelf(); builder.RegisterType<RestPublisher>().AsSelf(); builder.Register(c => { switch(Defs.AppSettings.PublisherType){ case "DB": c.Resolve<DbPublisher>(); break; case "REST": c.Resolve<RestPublisher>(); break; default: throw new NotSupportedException(); } }).As<IPublisher>();
-
使用名为注册
builder.RegisterType<DbPublisher>().Named<IPublisher>("DB"); builder.RegisterType<RestPublisher>().Named<IPublisher>("REST"); builder.Register(c => { var index = c.Resolve<IIndex<String, IPublisher>>(); return index[Defs.AppSettings.PublisherType] }.As<IPublisher>();
-
有条件注册
如果
Defs.AppSettings.PublisherType
在注册过程中被定义,你可以简单地有条件注册你的依赖:switch(Defs.AppSettings.PublisherType){ case "DB": builder.RegisterType<DbPublisher>().As<IPublisher>(); break; case "REST": builder.RegisterType<RestPublisher>().As<IPublisher>(); break; default: throw new NotSupportedException(); }
是'Defs.AppSettings.PublisherType'需要重新启动应用程序来更改配置值,也可以从随时间改变(请求之间例如)? – Steven