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BeforeDiscardInstance ​

This event is triggered before an "instance" (see below) is discarded.

Parameters ​

ParameterDescription
instidintValue, the ID of the discardedd instance.
classidintValue, the class ID of the discarded instance.
modelid (idValue, optional) -ue, the model ID of the discarded instance.
realinstanceidintValue, the "Real" ID of the instance (core internal ID).
realclassidintValue, the "Real" ID of the class (core internal ID).

Exit value: ​

|0|No abortion.| |-1|Abort without error.| |-2|Abort with error.| |greater than 0|Abort with core error code.|

Remarks ​

Instances are: Modeling objects, record rows, attribute profiles.

Mind the difference between deleting and discarding. Discarding means removing from memory, but the discarded instance may still exist as a part of its model (in the database). Deleting means, that the instance is removed from its model. Deleting implies discarding.

There should be no reason to abort a discard operation.

See Also ​

Example ​

The following example displays the predefined parameters before discarding an instance in an INFOBOX.

leo-grammar
	ON_EVENT "BeforeDiscardInstance" {
	SET id_InstId: (instid) 
	SET id_ClassId: (classid) 
	SET id_ModelId: (modelid)
	SET id_RealInstId:(realinstanceid)
	SET id_RealClassId: (realclassid)
	CC "AdoScript" INFOBOX ("Modelid:   " + STR(id_ModelId)  + "  ClassId:  " + STR(id_ClassId) + 
	"  InstanceId:   " + STR(id_InstId) + "  RealClassId:  " + STR(id_RealClassId) + "  RealInstanceId:  " 
	+ STR(id_RealInstId))  title:"You are discarding the instance..."
	}
	ON_EVENT "BeforeDiscardInstance" {
	SET id_InstId: (instid) 
	SET id_ClassId: (classid) 
	SET id_ModelId: (modelid)
	SET id_RealInstId:(realinstanceid)
	SET id_RealClassId: (realclassid)
	CC "AdoScript" INFOBOX ("Modelid:   " + STR(id_ModelId)  + "  ClassId:  " + STR(id_ClassId) + 
	"  InstanceId:   " + STR(id_InstId) + "  RealClassId:  " + STR(id_RealClassId) + "  RealInstanceId:  " 
	+ STR(id_RealInstId))  title:"You are discarding the instance..."
	}