see example below...
<asp:GridView ID="GridView2" runat="server" AutoGenerateColumns="false" DataSourceID="SqlDataSource2"GridLines="None"ShowFooter="false" ShowHeader="false">
<PagerSettings Mode="NextPrevious" NextPageText="Next" PreviousPageText="Previous" />
<Columns>
<asp:TemplateField>
<ItemTemplate>
/* Outer grid body*/
<asp:GridView ID="GridView2" runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource1" GridLines="None" ShowHeader="False">
<Columns>
<asp:TemplateField>
<ItemTemplate>
inner grid body
/* inner grid ends */
Implement whatever contents you want inside body of gridview(s)....
Thank you..