update panel full post back - asp.net

Question

i have the below code:
<asp:GridView runat="server" ID="GridView1" OnRowDataBound="gvChildGrid_RowDataBound" Width="1000px"
DataKeyNames="number" AllowSorting="false" style="font-size:15px;"
AutoGenerateColumns="False" BackColor="White" BorderColor="#E7E7FF" AllowPaging="true" HorizontalAlign="Center"
CellPadding="4" GridLines="none">
<%-- <PagerSettings Mode="NumericFirstLast" FirstPageText="first" PreviousPageText="previous" LastPageText="last" NextPageText="next" Position="bottom" PageButtonCount="2" />--%>
<AlternatingRowStyle BackColor="#F7F7F7" />
<Columns>
<asp:TemplateField HeaderText = "Select">
<ItemTemplate>
<a href="JavaScript:divexpandcollapse('div<%# Eval("number") %>');">
<img id="imgdiv" width = "20px" src="images/Alarm-Plus-icon.png" alt="" />
</a>
</ItemTemplate>
<HeaderStyle Font-Bold="True"/>
</asp:TemplateField>
<asp:TemplateField HeaderText = "Number">
<ItemTemplate>
<%# Eval("number")%>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText = "Name">
<ItemTemplate>
<%# Eval("name")%>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField>
<ItemTemplate>
<tr>
<td colspan="100%">
<div id="div<%# Eval("number") %>" style="display: none; position: relative; overflow: auto">
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:GridView ID="gvChildGrid" DataKeyNames="number" runat="server" BackColor="Transparent" AutoGenerateColumns="false" OnPageIndexChanging="gvChildGrid_PageIndexChanging"
style="Width:100% !important;" GridLines="None" Font-Names="times new roman" AllowPaging="True" CellPadding="4" AllowSorting="True">
<HeaderStyle BackColor="#8cc63e" Font-Bold="true" ForeColor="White" />
<Columns>
<asp:BoundField DataField="number" HeaderText="Mobile Number" >
<ItemStyle HorizontalAlign="Center" />
</asp:BoundField>
<asp:BoundField DataField="name" HeaderText="Name" >
<ItemStyle HorizontalAlign="Center" />
</asp:BoundField>
</Columns>
</asp:GridView>
</ContentTemplate>
</asp:UpdatePanel>
</div>
</td>
</tr>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
i'm using an update pannel for the second grid view gvChildGrid because i when i use the paging of this gridview i don't want the hole page to post back... only the grid view
but the problem is that the hole page is posting back
how can i fix this?

Answer 1

Add Update panel to <asp:TemplateField>. It may work I'm not sure.