Binding combox in gridview with selected value of another comboBox

BikerMonkey

Hi all, I hope I got the right forum... I can do what the subject states when the comboBox or DropDown is NOT in a gridview, as in the code below which populates the room DDL with the value that was selected in the building DDL

Protected Sub DDLbuilding_SelectedIndexChanged(sender As Object, e As EventArgs) Handles DDLbuilding.SelectedIndexChanged
'Create DataTable
Dim dtRooms As New DataTable() ' - Room Numbers
dtRooms.Columns.Add("Room", Type.GetType("System.String"))

    'Get Buildings for this campus
    RoomTable = RoomAdapter.GetRooms(DDLbuilding.SelectedValue)

    'Fill DataTable
    For Each RoomRow In RoomTable
        dtRooms.Rows.Add()
        dtRooms.Rows(dtRooms.Rows.Count - 1)("Room") = RoomRow.Room
    Next

    'bind DDLroom to datatable
    DDLroom.DataSource = dtRooms
    DDLroom.DataBind()
End Sub

but when the comboBox or DDL is in a gridview it throws the error "Databinding methods such as Eval(), XPath(), and Bind() can only be used in the context of a databound control". Here's what I have so far for the gridview comboBox

Protected Sub cbEQName_SelectedIndexChanged(sender As Object, e As EventArgs)

    'Get row index of selected comboBox
    Dim gvRow As GridViewRow = CType(CType(sender, Control).Parent.Parent, GridViewRow)
    Dim index As Integer = gvRow.RowIndex

    'Get selected value of selected comboBox
    EQname = TryCast(GVnewEquipment.Rows(index).FindControl("cbEQname"), AjaxControlToolkit.ComboBox).Text

    'Get new values of next comboBox from selected value of selected comboBox
    EquipmentTable = EquipmentAdapter.GetMfg(EQname)

    'Create DataTable
    Dim dtMfgs As New DataTable() ' - mfgs that are used by Equiptment name
    dtMfgs.Columns.Add("mfg", Type.GetType("System.String"))

    'Fill DataTable
    For Each EquipmentRow In EquipmentTable
        dtMfgs.Rows.Add()
        dtMfgs.Rows(dtMfgs.Rows.Count - 1)("mfg") = EquipmentRow.mfg
    Next

    'create ComboBox which will represent GVnewQuipment cbMfg comboBox
    Dim CB = DirectCast(GVnewEquipment.Rows(index).FindControl("cbMfg"), AjaxControlToolkit.ComboBox)

    'bind cbMfg to datatable
    CB.DataSource = dtMfgs
    CB.DataBind()

End Sub

Any and help is greatly appreciated!!

Lee