Each DataItem has the following triggers available:

The data item triggers are where most of the flow logic is placed for a report. Developer defined functions may be freely added but, generally, they will be called from within these following three triggers:

• OnPreDataItem(): This is the logical place for any preprocessing to take place that can't be handled in report or data item properties or in the two report preprocessing triggers.
• OnAfterGetRecord(): This is the data read and process loop. The code placed here has full access to the data of each record, one record at a time. This trigger is repetitively processed until the logical end of table is reached for this dataitem. This is where we would typically access data in related tables. This trigger is represented on our report Data Flow diagram as any one of the boxes labeled Data Item processing Loop.
• OnPostDataItem(): This executes after all the records in this data item are processed, unless the report is terminated by means of a User Cancelor by execution of a C/AL BREAK or QUIT function or by an error.