property ChartView.ExpandOnDblClk as Boolean
Expands or collapses a node when the user dbl clicks the node.

TypeDescription
Boolean A boolean expression that indicates whether the control expands or collapses a node when user dbl clicks the node. 
By default, the ExpandOnDblClk property is True. Use the HasButtons property to display the +/- buttons for nodes that contain child nodes. Use the HasButton property to hide the +/- button inside a particular node. Use the Expanded property to expand or collapse a node by code. The control fires the Expand event when user expands or collapse a node. Use the ButtonsAlign property to specify the position of +/- buttons inside nodes. The control fires the DblClick event when the user double clicks. Use the NodeFromPoint property to determine the node from the point.