Event adelline_before

Description

This event is called when a DELETE operation is requested on a (1,N) or (0,N) collection.

Context

In this context, the deletion is not yet done, and the event can reject the DELETE operation by returning in ASTATUS an error status ([V]CST_AERROR).

The following variables or properties are available in the context:

• this refers to the current class. All properties can be found by using the this.PROPERTY syntax.
• CURPRO is empty.
• AEVENT is equal to ADELLINE_BEFORE.
• CURPTH contains the collection code.
• ALINE contains the line position where the deletion must be done.

The different values possible for ALINE are:

• [V]CST_AFIRSTPOS if a line must be deleted at the first position of the collection.
• any other position between 1 and N-1 (N being the number of lines already present in the collection).

Take care that if you want to control the line that will be deleted, you have to use the AGETINDBYLINE method to get the physical position. This can be done by the following code:

$ADELLINE_BEFORE
 Local Integer LCONTROL, POSCONTROL
 If ALINE<>[V]CST_ALASTPOS
   If ALINE=[V]CST_AFIRST_POS
     LCONTROL=1
   Else
     LCONTROL=ALINE
   Endif
   POSCONTROL=fmet this.AGETINDBYLINE("COLLECT",LCONTROL)
   If POSCONTROL>0
     # Here you can control the properties of this.COLLECT(POSCONTROL) to decide if the insertion can be done
   Else
     # The position sent is not valid, raise an error or ignore
   Endif
 Else
     # This case is not possible because this position refers to a position for a line addition
 Endif