Just put these template field inside a grid view.
<asp:TemplateField>
<ItemTemplate>
<div id = "divItemTemplate" runat = "server">
<table>
<tr>
<td>
<asp:Label ID="lblRowNo" runat="server" Text='<%# Container.DataItemIndex + 1 %>'></asp:Label>
</td>
</tr>
</table>
</div>
</ItemTemplate>
<HeaderStyle/>
<ItemStyle/>
</asp:TemplateField>
Note: The Line Text='<%# Container.DataItemIndex + 1 %> ' will give you the count of rows in Gridview.