Sample beforelist event php rad classic

i want to check fieldname value in page event beforelist but no data or record can be debug? any idea ?

Hi,
In before view or list page events, no data has been gotten, so you can’t access the data. You can only access data in the after view or list events.
Add and edit event you can access data before since the data is submitted, and you can access that same data after it has been added or updated.