If you have no time, and you want things to work "magically"; go download Ajax Control Toolkit;
- Drop a link in your markup that would open the grid; name it
MyLink
- Define the two column'ed GridView inside a
Panel
.
<asp:Panel runat="server" ID="pnlGrid"><asp:GridView ...></asp:Panel>
- Drop
ModalPopupExtender
control from Ajax Control Toolkit in your markup.
- Add Panel's id in
ModalPopupExtender
's markup
<act:ModalPopupExtender ID="MyModalPopupExtender1" runat="server" TargetControlID="MyLink" PopupControlID="pnlGrid" style="display:none" OkControlID="MyOkButton"/>
Now clicking on the MyLink would open the Popup with GridView inside; dont forget to add GridView.EmptyDataText property, so that you'd know when there are no records to show.
Last, but not least, upon your page load, load the data from your database, and assign it your GridView.DataSource
This article is a good start.
Enjoy!