Homework

My code for this solution included the following logic in the sort event handler:

If ViewState("SortedColumn") = SortExpression And _
                 ViewState("SortOrder") = "ASC" Then
   ViewState("SortOrder") = "DESC"
Else
   ViewState("SortOrder") = "ASC"
End If
ViewState("SortedColumn") = SortExpression

and the following code in the FillAndBind() routine:

SqlDataAdapter1.SelectCommand.CommandText += " order by " + _
                 ViewState("SortedColumn") + " " + ViewState("SortOrder")

Finally, it set a default sort order (i.e., "ASC") in the page_load() function.

Personal Database Project

I accepted most anything reasonable here.