For Overview, please see my earlier post Introducing Extensions in Microsoft Dynamics NAV 2016
When you create extension package you can include new as well as modified objects.
In Microsoft Dynamics NAV 2016, these object types can be added and included in an extension:
You can modify these existing object types as permitted by your license:
- Action Items
You will not be able to add or modify any other object types in this version.
You are not allowed to delete any existing objects.
You will also need to be sure not to modify any existing C/AL code, including code in codeunits and in triggers on existing objects.
In case you want to modify existing code, use the new C/AL eventing model.
To know more about Events see by earlier posts:
This restriction is only on existing code and objects. However New pages, tables, and so on, can contain C/AL code as it is considered part of the new object.