how to correctly evaluate .GetType().IsInstanceOfType(typeof(Interface<>))

Question

How can I make code below return true ?

1. handler variable defined as an object on purpose to mimic the actual environment.

2. I already read https://stackoverflow.com/questions/12160460/when-is-obj-gettype-isinstanceoftypetypeofmyclass-true

void Main()
{
    object handler = new TestIntegrationEventHandler();
    Type eventType = typeof(TestIntegrationEvent);
    Type concreteType = typeof(IIntegrationEventHandler<>).MakeGenericType(eventType);
    Console.WriteLine(handler.GetType().IsInstanceOfType(concreteType));
}

public class TestIntegrationEvent : IntegrationEvent
{
}

public class IntegrationEvent
{
}

public class TestIntegrationEventHandler : IIntegrationEventHandler<TestIntegrationEvent>
{
    public async Task Handle(TestIntegrationEvent @event)
    {
    }
}

public interface IIntegrationEventHandler<in TIntegrationEvent> : IIntegrationEventHandler where TIntegrationEvent : IntegrationEvent
{
    Task Handle(TIntegrationEvent @event);
}

public interface IIntegrationEventHandler
{
}

Answer 1

It is the other way round!

private static void Main()
{
    object handler = new TestIntegrationEventHandler();
    Type eventType = typeof(TestIntegrationEvent);
    Type concreteType = typeof(IIntegrationEventHandler<>).MakeGenericType(eventType);
    Console.WriteLine(concreteType.IsInstanceOfType(handler));
    Console.ReadLine();
}

From the documentation for IsInstanceOfType :

Determines whether the specified object is an instance of the current Type.

So, you are asking whether IIntegrationEventHandler<TestIntegrationEvent> is an instance of type TestIntegrationEventHandler , which is false of course. Although I really think that the method's name does not help much...