Ext.Net.AccordionLayout.ExpandPanel C# (CSharp) Method

        public virtual void ExpandPanel(int index)
        {
            if (index >= this.Items.Count || index < 0)
            {
                throw new ArgumentOutOfRangeException("index");
            }

            foreach (PanelBase panel in this.Items)
            {
                if (!panel.Collapsed)
                {
                    panel.Collapsed = true;
                }
            }

            ((PanelBase)this.Items[index]).Collapsed = false;
        }
    }