Sort multiple columns in gridview

[jamie_pattison]

I am trying to sort a gridview which contains around 10 columns. I have the below code which works to an extent but i cant reverse the procedure (i.e. Ascend the row). In addition im not sure how i could sort multiple columns rather than just one?

page_Load
ViewState("sort") = ""
End Sub

    Private Sub Gridview1_Sorting(sender As Object, e As System.Web.UI.WebControls.GridViewSortEventArgs) Handles Gridview1.Sorting
        Dim dt As DataTable = GetCustomer

        If ViewState("sort") = "DESC" Then
            dt.DefaultView.Sort = e.SortExpression + " DESC"
            Gridview1.DataSource = dt.DefaultView
            Gridview1.DataBind()
        Else
            dt.DefaultView.Sort = e.SortExpression
            Gridview1.DataSource = dt.DefaultView
            Gridview1.DataBind()
        End If
    End Sub

 

[jamie_pattison]

Never mind i noticed i forgot to set the view state again..... Although if anyone knows how to sort multiple view then please advise.