Boundaries of a Recordset

Recordset supports the BOF and EOF properties to delineate the beginning and end, respectively, of the dataset. You can think of BOF and EOF as "phantom" records that are positioned at the beginning and end of the Recordset. Counting BOF and EOF, our sample Recordset would now look like this:

ProductID	ProductName	UnitPrice
BOF
7	Uncle Bob's Organic Dried Pears	30.0000
14	Tofu	23.2500
28	Rssle Sauerkraut	45.6000
51	Manjimup Dried Apples	53.0000
74	Longlife Tofu	10.0000
EOF

When a cursor moves past the last record, EOF is set to True; otherwise, its value is False. Similarly, when the cursor moves before the first record, BOF is set to True; otherwise, its value is False. These properties are commonly used to enumerate records in the dataset, as illustrated in the following JScript code fragment.

while (objRecordset.EOF != true)   
{  
   // Work on the current record.  
   ...  
   // Advance the cursor forward to the next record.  
   objRecordset.MoveNext();  
}  
or  
while (objRecordset.BOF != true)   
{  
   // Work on the current record.  
   ...  
   // Move the cursor to the previous record.  
   objRecordset.MovePrevious();  
}  

If both BOF and EOF are True, the Recordset object is empty. Both properties will be False for a newly opened, non-empty Recordset object. You can use the BOF and EOF properties together to determine if a Recordset object is empty or not, as shown in the following JScript code fragment.

if (objRecordset.EOF == true && objRecordset.BOF == true)  
{  
   WScript.Echo("we got an empty dataset.");  
}  
else  
{  
   WScript.Echo("we got a full dataset.");  
}  

This scheme works for all types of cursor and is independent of the underlying providers. If you attempt to determine the emptiness of a Recordset object by checking if its RecordCount property value is zero (0) or not, you must take precautions to use an appropriate cursor and provider that support returning of the number of records in the result.

If you delete the last remaining record in the Recordset object, the cursor is left in an indeterminate state. The BOF and EOF properties may remain False until you attempt to reposition the current record, depending upon the provider. For more information, see Deleting Records Using the Delete Method.