This sample demonstrates the default C1Accordion control behavior.

The first accordion pane in this sample is expanded by default (the SelectedIndex property value is zero).

If you wish to expand another accordion pane then, please, set the SelectedIndex property to the appropriate accordion pane.

Note that you can set the SelectedIndex property to -1 if you want to collapse all panes, e.g:

<C1Accordion:C1Accordion runat="server" 
			ID="C1Accordion1" 
			SelectedIndex="-1">