Vista - retrieve boundfield value in gridview Rowupdating event

In a Gridview control, I have several BoundFields, and also a couple of
TemplateFields.

In the Rowupdating event, I try to retrieve one of the BoundFields (i.e. 4th
column of the Gridview control) for comparision purpose. However; I got
null string everytime. On the other hand, I'm able to retrieve the
dropdownbox value in the TemplateField. I would like to know what I did
wrong with the BoundField. Thanks.

Code fragment:
Protected Sub gvLog_RowUpdating(ByVal sender As Object, ByVal e As
System.Web.UI.WebControls.GridViewUpdateEventArgs)

Dim gvRow As GridViewRow

Dim temp, temp1 As String


gvRow = grdLog.Rows(e.RowIndex)

temp1 = gvRow.Cells(4).Text