what is a good solid design aproch for creating web forms?

Right now I'm am working on a User Control/.ascx that populates a datagrid and allows you to filter data on type, page through the data, and view/edit/delete the data when you select the data. I'm not using the edit command/update commands of the grid. When selected index changes I change Panels. I have two panels nested in another panel. PanelGrid hold the grid and is visible from the start. PanelEdit is not visible. I have them switchng fine, and I can handle the data in the change over fine; but is this a good idea? I mean, it seems like it is. Well, except for the 3 copys of the data. ViewState, DataTable, and the DataGrid all have a copy copy copy.