Hi Sandip,
You can use
Update Panel[
^].
You can use following code:
<asp:TemplateField>
<FooterTemplate>
<asp:UpdatePanel ID="upnlBtnAdd" runat="server">
<asp:LinkButton ClientIDMode="static" runat="server" ID="btnAdd" Text="Add" OnClick="btnAdd_Click"></asp:LinkButton>
</asp:UpdatePanel>
</FooterTemplate>
</asp:TemplateField>