System.Object
   C1.WinUI.Viewer.GridLengthConverter
   C1.WinUI.Viewer.RectUtils
   C1.WinUI.Viewer.ToolMenuItem
   C1.WinUI.Viewer.TopMarginConverter
   Microsoft.UI.Xaml.DependencyObject
      Microsoft.UI.Xaml.UIElement
         Microsoft.UI.Xaml.FrameworkElement
            Microsoft.UI.Xaml.Controls.ContentPresenter
               C1.WinUI.Viewer.PagesPresenter
            Microsoft.UI.Xaml.Controls.Control
               C1.WinUI.Viewer.FlexViewer
               C1.WinUI.Viewer.FlexViewerPane
               C1.WinUI.Viewer.SearchToolBar
               C1.WinUI.Viewer.SelectionGripper
               C1.WinUI.Viewer.ViewHeader
               Microsoft.UI.Xaml.Controls.ItemsControl
                  Microsoft.UI.Xaml.Controls.Primitives.Selector
                     Microsoft.UI.Xaml.Controls.FlipView
                        C1.WinUI.Viewer.PagesFlipView
                     Microsoft.UI.Xaml.Controls.ListViewBase
                        Microsoft.UI.Xaml.Controls.ListView
                           C1.WinUI.Viewer.ToolMenu
   System.EventArgs
      C1.WinUI.Viewer.CustomToolEventArgs
      C1.WinUI.Viewer.HyperlinkHoveredEventArgs
      C1.WinUI.Viewer.OperationErrorEventArgs
      C1.WinUI.Viewer.SearchActionEventArgs
      System.ComponentModel.CancelEventArgs
         C1.WinUI.Viewer.HyperlinkClickedEventArgs
         C1.WinUI.Viewer.OutlineClickedEventArgs

Reference

C1.WinUI.Viewer Assembly