make navigation dynamically in listview

Hi

i make list view in asp.net

and want to dynamicallly from code behind , show 25 products  each page..and for other show navigation

i.e. 1  2   3  4  5   6   7    8   etc....

so on 2 click, show 26 to 50...and so on..

i want to make navigation from code behind and static ....

for exp.. if 200 products are there,,

show 1 to 25 , then navigation for  as :

1      2    3   4    5     6      7      8

I used

<asp:DataPager runat="server" ID="ItemDataPager" PageSize="25">
<Fields>
<asp:NumericPagerField ButtonCount="5" />
</Fields>
</asp:DataPager>

but this is static ..how to make dynamic ...

how to do this