How to catch a element in the ASPXGRIDVIEW Edit from via DetailRowExpandedChanged method of grid

How to catch a element in the ASPXGRIDVIEW Edit from via DetailRowExpandedChanged method of grid

ASPxPageControl pageCntrlInbox = (sender as ASPxGridView).FindDetailRowTemplateControl(e.VisibleIndex, "pageCntrlInbox") as ASPxPageControl;