'宣言
Public MustInherit Class _StepLineShapeViewsBuilder(Of TPointView As ISymbolPointView) Inherits _LineShapeViewsBuilder(Of TPointView) Implements ILineShapeViewsBuilder
public abstract class _StepLineShapeViewsBuilder<TPointView> : _LineShapeViewsBuilder<TPointView>, ILineShapeViewsBuilder where TPointView: ISymbolPointView