'宣言
Public MustInherit Class _BaseAnnotationOverlayDefinition(Of TOption As IAnnotationOverlayOption) Inherits _BaseOverlayDefinition(Of TOption) Implements IAnnotationOverlayDefinition, ILegendOverlayDefinition, IOverlayDefinition, IQueryInterface
public abstract class _BaseAnnotationOverlayDefinition<TOption> : _BaseOverlayDefinition<TOption>, IAnnotationOverlayDefinition, ILegendOverlayDefinition, IOverlayDefinition, IQueryInterface where TOption: IAnnotationOverlayOption