Datagrid flecha arriba y flecha abajo desplaza sobre la grilla

 
<%@ImportNamespace="Conexiones" %>
<scriptrunat="server">
dim controlcito as datagrid
PublicSub LLenar(ByVal sql AsString)
 
Dim obj AsNew Conexiones.sql_conexiones
obj.LLenarDataGrid(sql, DG_generico)
EndSub
 
Sub Page_load()
 
controlcito = Findcontrol("dg_generico") 
controlcito.focus()
controlcito.attributes.add("onKeyDown", "if(event.keyCode== 40) { document.getElementById('" & Me.id & "_hf_auxiliar_bajar').value = 1; form1.submit(); } else if(event.keyCode== 38) { document.getElementById('" & Me.id & "_hf_auxiliar_subir').value = 1; form1.submit(); } ")
 
If hf_auxiliar_subir.Value = 1 Then
 
Dim PonColor As System.Drawing.Color
PonColor = Drawing.Color.Red
 
If hf_auxiliar_2.Value > 0 Then
 
dg_generico.items(hf_auxiliar_1.value).backcolor = Drawing.Color.Transparent
Dim contador AsInteger
contador = hf_auxiliar_2.Value - 1
hf_auxiliar_1.value = contador
hf_auxiliar_2.Value = contador
DG_generico.Items(contador).BackColor = PonColor
hf_auxiliar_subir.Value = 0
controlcito = Findcontrol("dg_generico")
controlcito.focus() 
 
EndIf
EndIf
 
If hf_auxiliar_bajar.Value = 1 Then
 
dim cantidadposiciones asinteger
cantidadposiciones = dg_generico.items.count() - 1
 
If hf_auxiliar_2.Value < cantidadposiciones Then
 
DG_generico.Items(hf_auxiliar_1.Value).BackColor = Drawing.Color.Transparent
Dim contador AsInteger
Dim PonColor As System.Drawing.Color
PonColor = Drawing.Color.Red
contador = hf_auxiliar_2.Value + 1
hf_auxiliar_1.Value = contador
hf_auxiliar_2.Value = contador
DG_generico.Items(contador).BackColor = PonColor
hf_auxiliar_bajar.Value = 0
controlcito = FindControl("dg_generico")
controlcito.Focus()
 
EndIf
 
EndIf
 
EndSub
 
Sub DG_generico_itemcommand(ByVal s AsObject, ByVal e As DataGridCommandEventArgs) Handles DG_generico.ItemCommand
Dim iid AsInteger = Convert.ToInt32(e.Item.Cells(1).Text) 'Grab the ID from the hidden column 
SelectCase (CType(e.CommandSource, LinkButton)).CommandName
Case"Seleccionar"
 
dg_generico.items(hf_auxiliar_1.value).backcolor = Drawing.Color.Transparent
e.Item.BackColor = Drawing.Color.Red
hf_auxiliar_2.Value = e.Item.ItemIndex
hf_auxiliar_1.value = iid
 
CaseElse
' Do nothing 
EndSelect
EndSub
</script>
 
<htmlxmlns="http://www.w3.org/1999/xhtml">
<asp:DataGridid="DG_generico"AutoGenerateColumns="true"Width="100%"align="center"runat="server"BorderColor="Black"BorderWidth="1">
<columns>
 
<asp:TemplateColumnItemStyle-Width="20px"ItemStyle-BorderColor="Black"ItemStyle-BorderWidth="1"ItemStyle-Wrap="true">
<HeaderStyleBorderColor="Black"BorderWidth="1"/>
<ItemTemplate>
 
<asp:linkbuttonCausesValidation="false"id="cmdSel"CommandName="Seleccionar"runat="server">
<imgsrc="imagenes/23.png"alt='Seleccionar'width="20"width="20"/>
</asp:linkbutton>
 
</ItemTemplate>
<ItemStyleWrap="True"Width="20px"></ItemStyle>
</asp:TemplateColumn>
 
</columns>
</asp:DataGrid>
 
<asp:HiddenFieldrunat="server"id="hf_auxiliar_bajar"Value="0"/>
<asp:HiddenFieldrunat="server"id="hf_auxiliar_subir"Value="0"/>
<asp:HiddenFieldrunat="server"id="hf_auxiliar_1"Value="0"/>
<asp:HiddenFieldrunat="server"id="hf_auxiliar_2"Value="-1"/>
 
</html>