Bookmarks and SelBookmarks provide a means to track records. This is necessary when you program special functionality into an application, such as allowing the end user to manually select several discontiguous records, and performing a bulk update of the selected records. In that case, you will need to track which records have been selected, and you would therefore use the SelBookmarks collection and its properties.
Two functions, the CellText and CellValue methods, require bookmarks to perform properly.
The SelBookmarks collection contains the bookmarks of all selected records. When the end user manually selects records (by holding down the CTRL key while clicking) the bookmark for each selected record is added to the collection. Using standard iteration methods, you can determine what has been selected, store the bookmarks (in case you need to restore a value), and perform the operation:
Dim i as Integer ' Counter
Dim intCount As Integer
intCount = DataGrid1.SelBookmarks.Count - 1
ReDim arrSelBK(intCount) ' Declare array to hold bookmarks.
For i = 0 To intCount
ArrSelBK(i) = DataGrid1.SelBookmarks(i)
' Perform operations here. If the operations must be
' cancelled, exit the loop and use the array to
' rollback the changes.
Next i
You can also programmatically select records by adding them to the collection. For example, you may have a grid that shows all of the orders by a certain customer. To highlight all of the records where the customer spent more than $100, filter the records, and add the resulting bookmarks to the SelBookmarks collection.
Dim rs As Recordset
Set rs = Adodc1.Recordset
While Not rs.EOF
If rs!SupplierID = 12 Then
DataGrid1.SelBookmarks.Add rs.Bookmark
End If
rs.MoveNext
Wend