ModalPopupExtender

<ajaxtoolkit:modalpopupextender id="PopupControlExtender1" runat="server" dropshadow="false"backgroundcssclass="main_alfa" cancelcontrolid="btncln" targetcontrolid="btntrasactionlist"
 <asp:panel id="Pnltrasactionlist1" runat="server" style="display: none; visibility: hidden">

 <cc1:myGridView ID="OdgOrderTrascationList" runat="server" Width="100%" DataKeyNames="TransId"GridLines="None" AllowPaging="True" AllowSorting="True" AutoGenerateColumns="False"BorderStyle="None" SortAscImageUrl="~/Images/sort_asc.png" SortDescImageUrl="~/Images/sort_desc.png"CellPadding="3" AllowCustomPaging="false" Visible="false"><Columns><asp:BoundField DataField="TransId" HeaderText="Transaction ID" /><asp:BoundField DataField="CreditCardCharge" HeaderText="CC Charge" DataFormatString="{0:c2}" /><asp:BoundField DataField="RefundAmount" HeaderText="Refund Amount" DataFormatString="{0:c2}" /><asp:BoundField DataField="IsRefund" HeaderText="Refund" /><asp:BoundField DataField="TransactionDate" HeaderText="Transaction Date/Time" /></Columns>
 
<asp:LinkButton ID="btncln" runat="server" Text="Cancel"></asp:LinkButton>
 <asp:button id="btntrasactionlist" runat="server" text="Transaction History" /></asp:panel></cc1:myGridView>
<strong> Transaction Details:</strong> <br /> popupcontrolid="Pnltrasactionlist1" />