Refer to DrawPage example.

Selects or deselects the specified zone in the specified page and draws the results into the specified Graphics object. To draw a page, call DrawPage method. To select a zone by specifying a hit point, call SelectZoneByPoint.
This method will update the SelectedZoneIndex property value as follows:

• If the selectZone parameter value is true, then SelectedZoneIndex property will be updated to equal to zoneIndex parameter value
• If the selectZone parameter value is false, then SelectedZoneIndex property will be -1.

For more information, refer to Drawing Pages and Zones.

Reference

RasterDocumentEngine Class
RasterDocumentEngine Members
AddZone Method
UpdateZone Method
DrawPage(Graphics,Int32,Rectangle,Rectangle,Rectangle,Rectangle,RasterPaintProperties) Method
SelectZoneByPoint(Graphics,Int32,Point) Method
RemoveSelectedZone Method
UpdateZoneArea Method
GetSelectedZoneData Method
ActivePage Property