Business and integration events are raised by C/AL code to notify subscribers about the execution of certain actions in application business logic. For example, these kinds of events in codeunit 90 Purch.-Post, are OnBeforePostPurchaseDoc and OnAfterPostPurchaseDoc. The first one is raised when a purchase document is submitted to the posting procedure, before processing, and the second event is called immediately after the document is processed.
Codeunit 22 Item Jnl.-Post Line raises a corresponding event when inserting a certain type of a ledger entry. Now we will see how to update an item ledger entry, filling in custom fields, by subscribing to an integration event to avoid modifying the application code in codeunit 22.