BOF, EOF Properties

See Also    Example    Applies To

• BOF returns a value that indicates whether the current record position is before the first record in a CdbRecordset object.
  
  
• EOF returns a value that indicates whether the current record position is after the last record in a CdbRecordset object.

Syntax

BOOLGetBOF(VOID);

BOOLGetEOF(VOID);

Remarks

The BOF property returns True if the current record position is before the first record, and False if the current record position is on or after the first record.

The EOF property returns True if the current record position is after the last record, and False if the current record position is on or before the last record.

You can use the BOF and EOF properties to determine whether a CdbRecordset object contains records or whether you've gone beyond the limits of a CdbRecordset object when you move from record to record.

The location of the current record pointer determines the BOF and EOF return values.

If either the BOF or EOF property is True, there is no current record.

If you open a CdbRecordset object containing no records, the BOF and EOF properties are set to True, and the CdbRecordset object's RecordCount property setting is 0. When you open a Recordset object that contains at least one record, the first record is the current record and the BOF and EOF properties are False; they remain False until you move beyond the beginning or end of the CdbRecordset object by using the MovePrevious or MoveNext method, respectively. When you move beyond the beginning or end of the CdbRecordset, there is no current record or no record exists.

If you delete the last remaining record in the CdbRecordset object, the BOF and EOF properties may remain False until you attempt to reposition the current record.

If you use the MoveLast method on a CdbRecordset object containing records, the last record becomes the current record; if you then use the MoveNext method, the current record becomes invalid and the EOF property is set to True. Conversely, if you use the MoveFirst method on a CdbRecordset object containing records, the first record becomes the current record; if you then use the MovePrevious method, there is no current record and the BOF property is set to True.

Typically, when you work with all the records in a CdbRecordset object, your code will loop through the records by using the MoveNext method until the EOF property is set to True.

If you use the MoveNext method while the EOF property is set to True or the MovePrevious method while the BOF property is set to True, an error occurs.

This table shows which Move methods are allowed with different combinations of the BOF and EOF properties.

Allowing a Move method doesn't mean that the method will successfully locate a record. It merely indicates that an attempt to perform the specified Move method is allowed and won't generate an error. The state of the BOF and EOF properties may change as a result of the attempted Move.

An OpenRecordset method internally invokes a MoveFirst method. Therefore, using an OpenRecordset method on an empty set of records sets the BOF and EOF properties to True. (See the following table for the behavior of a failed MoveFirst method.)

All Move methods that successfully locate a record will set both BOF and EOF to False.

In a Microsoft Jet workspace, if you add a record to an empty CdbRecordset, BOF will become False, but EOF will remain True, indicating that the current position is at the end of Recordset. In an ODBCDirect workspace, both BOF and EOF will become False, indicating that the current position is on the new record.

Any Delete method, even if it removes the only remaining record from a CdbRecordset, won't change the setting of the BOF or EOF property.

The following table shows how Move methods that don't locate a record affect the BOF and EOF property settings.