DevGuru ADO Recordset::WillMove Event

EVENT: Recordset::WillMove

WillMove (adReason, adStatus, pRecordset)

The WillMove event can be fired before the current position inside the Recordset will be changed by an operation that involves a call to the AddNew, Move, MoveFirst, MoveLast, MoveNext, MovePrevious, Open, or the Requery methods or to the AbsolutePage, Bookmark, Filter, or Index properties. This event can be triggered for both child and parent Recordset objects.

In contrast, the MoveComplete event can be fired after a position change occurs in the Recordset involving the same methods.

An event is simply a subroutine that can be called automatically after a specific operation has occurred. This subroutine can contain any code that you need to run when the event occurs. The subroutine will only be called if it is included in your code.

There are three parameters passed to this event.

The adReason parameter is one of six of the EventReasonEnum constants that describe what pending operation caused this event to fire. Note that there is a total of fifteen of these constants, but only the following six can actually be used by this parameter.

EventReasonEnum Constants

Constant	Value	Description
adRsnMove	10	The record pointer has been moved in the Recordset
adRsnMoveFirst	12	The record pointer has been moved to the first record in the Recordset
adRsnMoveLast	15	The record pointer has been moved to the last record in the Recordset
adRsnMoveNext	13	The record pointer has been moved to the next record in the Recordset
adRsnMovePrevious	14	The record pointer has been moved to the previous record in the Recordset
adRsnRequery	7	The Recordset has been requeried

The adStatus parameter is one of the EventStatusEnum constants that describes the current status of the event. If the action that triggered this event was successful, then the agrument will be set to adStatusOK. If the pending operation cannot be cancelled, it will be set to adStatusCantDeny.

EventStatusEnum Constants

Constant	Value	Description
adStatusCancel	4	Cancels the operation that fired the event
adStatusCantDeny	3	Cannot cancel pending operation
adStatusErrorsOccurred	2	Indicates that warnings and/or errors occurred
adStatusOK	1	The operation that fired the event was successful
adStatusUnwantedEvent	5	The operation that generated the event cannot generate future events

The pRecordset parameter is the Recordset object to which this event applies.

Code (Visual Basic):
' Use the WithEvents keyword to designate that events
' can be handled by this Recordset object
Dim WithEvents objRecSet As ADODB.Recordset

' Note how the object name, objRecSet, is incorporated into the event Sub name
Private Sub objRecSet_WillMove( adReason As ADODB.EventReasonEnum, _
   adStatus As ADODB.EventStatusEnum, _
   ByVal pRecordset As ADODB.Recordset )

' place any code you desire here, for example
If adReason = adRsnRequery Then
   adStatus = adStatusCancel
End If

End Sub