What's the purpose of EventArgs as base class in the event pattern?

Question

The classic general C# event has these parameters:

(object sender, EventArgs e)

I can implement an event with a more specific signature for the e argument, deriving for EventArgs.

Now, what's the purpose of a base class like EventArgs? I mean... it's empty. No base/abstract/virtual properties, nor fields, or something else.

Why the parameters of a basic event aren't just like below?

(object sender, object eventArgs)

That is, why all the event with some implemented and specific event-args parameter derive it from EventArgs and not from a simple object?

The above question is mirrored with the following one. The event delegate in the generic form is:

delegate void EventHandler<TEventArgs>(object sender, TEventArgs e)

and no restrictions are put on the parameter e. But I would have expected something like where TEventArgs : EventArgs, to be coherent...

Answer 1

Object wouldn't preclude value types like int, double, etc. Which would introduce boxing and un-boxing issues. The choice of using a base class over object is a choice to enforce the passing of strongly typed objects throughout an API.

I tend to cringe when I see pervasive use of the object type as it kind of defeats the whole point of using a strongly typed programming language, you might as well go program in javascript, although anyone remotely familiar with javascript will know they are striving towards a strongly typed programming paradigm.

EDIT: To elaborate further on the distinction between an event model passing reference types vs value types. When a delegate handling an event alters the data for an event, which many people frequently do when raising an event, if the data passed were a value type you would then need to start thinking about whether you're changing a copy passed by value or the original reference to the value type, of course you would hope you are altering the original. Enforcing the passing of reference types is a pretty critical design decision in the .NET event model.