By default, the AllowSelectObjectRect is exLeftClick + exALTKey, which indicates that the user can start dragging a rectangle by clicking the left mouse button while keeping the ALT key, to select the elements ( Selectable property is True ) that intersect the rectangle. Set the AllowSelectObjectRect property on exDisallow to prevent selecting elements using the dragging rectangle. The AllowSelectObjectRect property specifies the keys combination so the user can select the elements from the dragging rectangle. Use the Background(exSelectElementRectColor) property to specify the color to show the rectangle that highlights the elements that intersect the dragging rectangle. The AllowSelectObject property indicates the keys combination to allow user selecting new elements. The AllowToggleSelectKey property indicates the key to be used so the user can toggle a selected element. The AllowSelectNothing property indicates whether the selection is cleared once the user clicks any empty area on the surface. The SelectAll method selects all elements in the chart. Use the UnselectAll method to unselect all elements on the surface. The SingleSel property specifies whether the surface allows selecting one or multiple elements. The SelCount property counts the number of selected elements. The SelElement property returns the selected element based on its index in the selected elements collection. The Selection property sets or gets a safe array of selected elements.

The following screen shot shows the selection rectangle: