You should use an UpdatePanel
to update your data.
using the UpdatePanel control, you can enable a Web page to participate in partial-page updates without writing any client script. If you want, you can add custom client script to enhance the client user experience. When you use an UpdatePanel control, the page behavior is browser independent and can potentially reduce the amount of data that is transferred between client and server.
Look at how to set different triggers to use the menu buttons to trigger the udpate.