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