SignalR 结构图依赖解析器(为 Microsoft.AspNet.SignalR.Messaging.IMessageBus 指定)

Question

我该如何解决这个错误？

版本

Microsoft.AspNet.SignalR.Core 2.2.0，结构图 3.1.4.143

global.asax signalR 依赖解析

// SIGNALR DEPENDENCY RESOLVER
        GlobalHost.DependencyResolver = new StructureMapSignalRDependencyResolver(Container ?? ObjectFactory.Container);

StructureMapSignalRDependencyResolver

public class StructureMapSignalRDependencyResolver : DefaultDependencyResolver
{
    private readonly IContainer _container;
    public StructureMapSignalRDependencyResolver(IContainer container)
    {
        _container = container;
    }

    public override object GetService(Type serviceType)
    {
        object service = null;
        //Below is a key difference between this StructureMap example, GetInstance is used for concrete classes.
        if (!serviceType.IsAbstract && !serviceType.IsInterface && serviceType.IsClass)
        {
            //If the type is a concrete type we get here...
            service = _container.GetInstance(serviceType);
        }
        else
        {
            // Non concrete resolution which uses the base dependency resolver if needed.
            service = _container.TryGetInstance(serviceType) ?? base.GetService(serviceType);
        }
        return service;
    }

    public override IEnumerable<object> GetServices(Type serviceType)
    {
        var objects = _container.GetAllInstances(serviceType).Cast<object>();
        return objects.Concat(base.GetServices(serviceType));
    }
}

错误

没有注册默认实例，无法自动确定类型“Microsoft.AspNet.SignalR.Messaging.IMessageBus”

没有为 Microsoft.AspNet.SignalR.Messaging.IMessageBus 指定配置

1.) new AckSubscriber(IMessageBus 的默认值，IAckHandler 的默认值)2.) Microsoft.AspNet.SignalR.Infrastructure.AckSubscriber3.) Microsoft.AspNet.SignalR.Infrastructure.AckSubscriber 实例4.) Container.GetInstance(Microsoft.AspNet.SignalR.Infrastructure.AckSubscriber)

Answer 1

首先尝试从基类解析。

    public override object GetService(Type serviceType)
    {
        if (serviceType == null)
            return null;

        var service = base.GetService(serviceType);
        if (service != null) return service;

        return (!serviceType.IsAbstract && !serviceType.IsInterface && serviceType.IsClass)
            ? container.GetInstance(serviceType)
            : container.TryGetInstance(serviceType);
    }