通过反射调用方法时无效的参数

Question

我想用反射调用Prism EventAggregator，因为事件有效载荷是在运行时确定的。

下面是使用EventAggregator正常方式：

 [TestMethod] 
    public void WhenEventIsPublishedTheSubscriberReceivesIt() 
    { 
     var eventAggregator = new EventAggregator(); 

     eventAggregator.GetEvent<PubSubEvent<string>>().Subscribe(Subscription); 
     eventAggregator.GetEvent<PubSubEvent<string>>().Publish(Constants.TestSymbol); 

     Assert.IsTrue(this.subscriptionReceived); 
    } 

    private void Subscription(string data) 
    { 
     this.subscriptionReceived = true; 
    } 

我这样做：

  var commandHandlerLocator = this.container.Resolve<ICommandHandlerLocator>(); 

     var t = command.GetType(); 

     dynamic commandHandler = commandHandlerLocator.GetType() 
      .GetMethod("GetCommandHandler") 
       .MakeGenericMethod(command.GetType()).Invoke(commandHandlerLocator, null); 

     IEnumerable<IEvent> events = commandHandler.Execute(command); 

     foreach (var @event in events) 
     { 
      var typedEvent = typeof(PubSubEvent<>).MakeGenericType(@event.GetType()); 

      dynamic pubSubEvent = this.eventAggregator.GetType() 
       .GetMethod("GetEvent") 
        .MakeGenericMethod(typedEvent).Invoke(this.eventAggregator, null); 

      pubSubEvent.Publish(@event); 
     } 

看起来好像没什么问题。但是，当我执行最后一行“（pubSubEvent.Publish（@event）;”我得到的例外，发布方法被称为无效参数任何想法为什么@ event参数是无效的

关心！ 。

Answer 1

找到了答案，我需要强烈键入@event：

 private void Publish<T>(T @event) where T : IEvent 
    { 
     var eventAggregator = new EventAggregator(); 
     var pubSubEventType = typeof(PubSubEvent<>).MakeGenericType(typeof(T)); 

     dynamic pubSubEvent = eventAggregator.GetType() 
        .GetMethod("GetEvent") 
         .MakeGenericMethod(pubSubEventType).Invoke(eventAggregator, null); 

     pubSubEvent.Publish(@event); 
    }