给出以下解析IProcessor实例的代码

如何让autofac为我的服务使用者解决并创建这些服务？
我需要使用autofac才能使用此功能,或者需要与此功能类似的东西才能为相应的商品创建相关策略.这些策略需要以正确解决其依赖性的方式来创建.

理想情况下,这需要在应用程序的COMPOSITION ROOT中发生.
下面的代码未正确使用容器来构建实例.实际代码中的StrategyA和StrategyB将具有自己的依赖性.当处置消费者时,也将需要处置它们.

容器
我已经尝试过此操作,但收到一条错误消息,指出解析操作已经发生.

var builder = new Autofac.ContainerBuilder();
builder.RegisterType<StrategyA>().As<IProcessor>().Keyed<IProcessor>(typeof(ItemA).Name).InstancePerDependency();
builder.RegisterType<StrategyB>().As<IProcessor>().Keyed<IProcessor>(typeof(ItemB).Name).InstancePerDependency();
builder.Register<Func<string, IProcessor>>(c => (s) => c.ResolveKeyed<IProcessor>(s));
builder.RegisterType<MyServiceConsumer>().As<IConsumer>();

var container = builder.Build();
var consumer = container.Resolve<IConsumer>().DoStuff(new ItemA()).Dump();

服务消费者.

public class MyServiceConsumer : IConsumer {
    Func<string, IProcessor> processor;
    public MyServiceConsumer(Func<string, IProcessor> processor) {
        //processor.Dump("px");
        this.processor = processor;
    }
    public string DoStuff(IItem item) {
        return processor(item.GetType().Name).ProcessItem(item);
    }
}

这是接口.

public interface IConsumer { string DoStuff(IItem item); }
public interface IProcessor { string ProcessItem(IItem item); }
public interface IItem { string Name { get; } }
public interface IItemStrategy<in T> : IProcessor where T : IItem { string ProcessItem(T item); }

这是具体的类.

public class ItemA : IItem { public string Name { get { return "A"; } } public string UniqueA { get { return "+ UA"; } } }
public class ItemB : IItem { public string Name { get { return "B"; } } public string UniqueB { get { return "+ UB"; } } }

战略实施.
我希望我正确地应用了模式,理想情况下我确实想要强类型策略吗？

public class StrategyA : IItemStrategy<ItemA> { 
    string IProcessor.ProcessItem(IItem item) { Debug.Assert(item is ItemA); return this.ProcessItem((ItemA)item); }
    public string ProcessItem(ItemA item) { return "PA " + item.Name + item.UniqueA; } 
}
public class StrategyB : IItemStrategy<ItemB> { 
    string IProcessor.ProcessItem(IItem item) { Debug.Assert(item is ItemB); return this.ProcessItem((ItemB)item); }
    public string ProcessItem(ItemB item) { return "PB " + item.Name + item.UniqueB; } 
}

解决方法:

我已经知道了.
提示是在这里autofac registration issue in release v2.4.5.724

var builder = new Autofac.ContainerBuilder();
builder.RegisterType<StrategyA>().As<IProcessor>().Keyed<IProcessor>(typeof(ItemA).Name).InstancePerDependency();
builder.RegisterType<StrategyB>().As<IProcessor>().Keyed<IProcessor>(typeof(ItemB).Name).InstancePerDependency();
builder.Register<Func<string, IProcessor>>(c => {
    var ctx = c.Resolve<IComponentContext>();
    return (s) => ctx.ResolveKeyed<IProcessor>(s);
});
builder.RegisterType<MyServiceConsumer>().As<IConsumer>();

var container = builder.Build();

var consumer = container.Resolve<IConsumer>().DoStuff(new ItemB()).Dump();