$Sender->DiscussionID vs $Sender->EventArguments['Discussion']->DiscussionID

xatrix

I'm a little confused about these two. I needed to set a plugin's class property and had to perform a SQL query using the current DiscussionID. By trial and error I discovered that I need to use $Sender->DiscussionID with, for lack of a better word, "constructor" events (like DiscussionController_Render_Before) and Sender->EventArguments['Discussion']->DiscussionID with regular events.

Can someone tell me what's the difference and why do they return different values at different stages of execution?

judgej

I think it all just comes down to the way the events are called. When the events are called from an object that has context, e.g. a discussion controller, then the discussion ID is very likely to be in the Sender (since the Sender is the controller that called the event).

When events are called from more generic places, such as theme templates or generic helper functions, then there is less context - values such as the discussion ID are more likely to only exist as variables in the caller, and so need to be passed into the event as EventArguments in order for the event to see them.

Similarly, if an event is called up from a controller (Comments, say) in a loop, then the ID for the loop will likely be passed in as an EventArgument.

That's my observation at least, but I don't think there is any hard and fast rule. It just needs some inspection of the Sender code.

Linc

Yeah, generally EventArguments is used by fired events to pass along additional variables that otherwise wouldn't exist as properties of the object being passed as the $Sender. It's an ad hoc way of providing more data as it's needed.

xatrix

Thanks for the replies guys.

That's my observation at least, but I don't think there is any hard and fast rule. It just needs some inspection of the Sender code.

So basically print_r and echos?

Tim

Yes. And don't be afraid to look for the FireEvent() call in your IDE and go and see what is being assigned to EventArguments. That is usually the best way to see whats going on.

NabUser

Im trying to get discusision id on base render without any luck

x00

@NabUser start a new discussion