Windows.UI.Xaml.Controls.ScrollViewer.ZoomToFactor C# (CSharp) Method

		public extern void ZoomToFactor([In] float factor);
		public extern void InvalidateScrollInfo();

        /// <summary>
        /// スクロールビューを1段階縮小する
        /// </summary>
        /// <param name="scrollViewer"></param>
        private void scaleDownScrollViewer(ScrollViewer scrollViewer)
        {
            float factor = scrollViewer.ZoomFactor;
            if (factor <= this.ViewModel.MinZoomFactor)
            {
                return;
            }

            scrollViewer.ZoomToFactor(factor - ZOOM_UPDOWN_UNIT);
        }