Ajax Control Toolkit - Programmatically expand CollapsiblePanelExtender

Issue:
Expand a collapsible panel programmatically with use of a button or linkbutton other than the already assigned ExpandControlID control.



Solution: 

protected void expandCollapsiblePanelButton_Click(object sender, EventArgs e)

{

    // expand

    testCollapsiblePanelExtender.Collapsed = false;

    testCollapsiblePanelExtender.ClientState = "false";

}