c# - SignalR 和类型化对象

Question

我有一个非常基本的自托管网络服务，使用 SignalR 2.x具有以下配置:

服务器:

internal class WebService
{
    public void Configuration( IAppBuilder app )
    {
        var config = new HttpConfiguration { DependencyResolver = new ControllerResolver() };
        config.Formatters.XmlFormatter.SupportedMediaTypes.Clear();
        config.Formatters.JsonFormatter.SerializerSettings.TypeNameHandling = TypeNameHandling.Objects;
        config.Routes.MapHttpRoute( "Default", "{controller}/{id}", new { id = RouteParameter.Optional } );
        app.UseWebApi( config );
        app.MapConnection<EventDispatcher>( "", new ConnectionConfiguration { EnableCrossDomain = true } );

        GlobalHost.DependencyResolver.Register(typeof(JsonSerializer), () => JsonSerializer.Create(new JsonSerializerSettings
                                            {
                                                TypeNameHandling = TypeNameHandling.All
                                            }));

        app.MapHubs();
    }
}

发送消息的服务器代码:

public class Notifier
{
    static readonly IPersistentConnectionContext Context = GlobalHost.ConnectionManager.GetConnectionContext<EventDispatcher>();

    public static void NotifyAll( NotificationType type, object obj )
    {
        Context.Connection.Broadcast( ConstructEvent( type, obj ) );
    }

    public static object ConstructEvent( NotificationType type, object obj )
    {
        var notevent =  new { Event = type.ToString(), Data = obj };
        return notevent;
    }
}

客户:

void connect()
{
    var _eventHandler = new Connection(Address);
    _eventHandler.JsonSerializer.TypeNameHandling = TypeNameHandling.Objects;
    _eventHandler.Received += eventHandler_Received;
    _eventHandler.Start().Wait();
}

Web 服务很好地返回类型化 JSON，但 SignalR 发送的更新是纯 JSON。我在这里遗漏了什么吗？

Answer 1

虽然整个设置相当深奥，但对于那些感兴趣的人来说，这里是解决方案。

我认为问题是由使 GlobalHost.ConnectionManager.GetConnectionContext 静态化引起的。通过这样做，我认为我在正确设置 WebService DependencyResolver 之前创建了一个 PersistentConnection (尽管我不确定这是为什么)。通过为每个事件再次获取 ConnectionContext 来解决该问题:

public class Notifier
{
    public static void NotifyAll(NotificationType type, object obj)
    {
        var context = GlobalHost.ConnectionManager.GetConnectionContext<EventDispatcher>();
        var output = ConstructEvent(type, obj);
        context.Connection.Broadcast(output);
    }

    protected static object ConstructEvent(NotificationType type, object obj)
    {
        var notevent = new { Event = type.ToString(), Data = obj };
        return notevent;
    }
}

而不是:

public class Notifier
{
    static readonly IPersistentConnectionContext Context = GlobalHost.ConnectionManager.GetConnectionContext<EventDispatcher>();

    public static void NotifyAll(NotificationType type, object obj)
    {
        var output = ConstructEvent(type, obj);
        Context.Connection.Broadcast(output);
    }

    protected static object ConstructEvent(NotificationType type, object obj)
    {
        var notevent = new { Event = type.ToString(), Data = obj };
        return notevent;
    }
}