自动注册泛型接口的所有实现

Question

我当前的注册代码：

Assembly web = Assembly.Load("MyAssembly");
types.AddRange(web.GetTypes());
//etc.
foreach (var theInterface in types.Where(t => t.IsInterface))
{
    var assignableType = types.Where(t => theInterface.IsAssignableFrom(t) && t != theInterface);
    foreach (var type in assignableType)
    {
        container.RegisterType(theInterface, type);
    }
}

我的通用接口及其实现：

public interface IDomainEventHandler<in T>
{
    void Handle(T message);
}
public class DomainEventHandler1 : IDomainEventHandler<PhilTest1>
{
    public void Handle(PhilTest1 message)
    {
        throw new System.NotImplementedException();
    }
}
public class DomainEventHandler2 : IDomainEventHandler<PhilTest2>
{
    public void Handle(PhilTest2 message)
    {
        throw new System.NotImplementedException();
    }
}
public class DomainEventHandler3 : IDomainEventHandler<PhilTest2>
{
    public void Handle(PhilTest2 message)
    {
        throw new System.NotImplementedException();
    }
}
public class PhilTest1
{
}
public class PhilTest2
{
}

以下是我将如何解决的简化版本：

IEnumerable<IDomainEventHandler<PhilTest2>> listeners = Container.ResolveAll<IDomainEventHandler<PhilTest2>>();
IEnumerable<IDomainEventHandler<PhilTest1>> listeners2 = Container.ResolveAll<IDomainEventHandler<PhilTest1>>();

这不起作用——解析后listeners和listeners2都为空。这并不意外。

在温莎，我可以做这样的事情：

container.Register(AllTypes.FromAssemblyNamed("MyAssembly").BasedOn(typeof(IDomainEventHandler<>)).WithService.Base());

如何在Unity中注册IDomainEventHandler的所有实例？我更愿意保留现有的注册代码（如果可能的话）。

Answer 1

有点痛苦，但我最终通过谷歌和调试拼凑起来：

注册：

    IEnumerable<Type> handlers = types.Where(t => IsAssignableToGenericType(t, typeof(IDomainEventHandler<>)) && !t.IsInterface);
    foreach (var handler in handlers)
    {
        container.AddNewExtension<OpenGenericExtension>()
                    .Configure<IOpenGenericExtension>()
                    .RegisterClosedImpl(typeof (IDomainEventHandler<>), handler);
    }

IsAssignableToGenericType方法：

    private static bool IsAssignableToGenericType(Type givenType, Type genericType)
    {
        var interfaceTypes = givenType.GetInterfaces();
        foreach (var it in interfaceTypes)
        {
            if (it.IsGenericType && it.GetGenericTypeDefinition() == genericType)
                return true;
        }
        if (givenType.IsGenericType && givenType.GetGenericTypeDefinition() == genericType)
            return true;
        Type baseType = givenType.BaseType;
        if (baseType == null) return false;
        return IsAssignableToGenericType(baseType, genericType);
    }

以及扩展。请注意，如果我不使用名称进行注册，那么只有一种类型将保持注册状态。我相信这是故意的？

public interface IOpenGenericExtension : IUnityContainerExtensionConfigurator
{
    void RegisterClosedImpl(Type openGenericInterface, Type closedType);
}
public class OpenGenericExtension : UnityContainerExtension, IOpenGenericExtension
{
    protected override void Initialize() {}
    public void RegisterClosedImpl(Type openGenericInterface, Type closedType)
    {
        closedType.GetInterfaces().Where(x => x.IsGenericType)
                  .Where(x => x.GetGenericTypeDefinition() == openGenericInterface)
                  .ToList()
                  .ForEach(x => Container.RegisterType(x, closedType, closedType.Name));
    }
}