'宣言 Protected Overridable Function GetItemOffset( _ ByVal index As Integer, _ ByVal angleAxis As CategoryAngleAxis, _ ByVal windowRect As Rect, _ ByVal viewportRect As Rect, _ ByVal effectiveViewportRect As Rect _ ) As Double
protected virtual double GetItemOffset( int index, CategoryAngleAxis angleAxis, Rect windowRect, Rect viewportRect, Rect effectiveViewportRect )