Set this property to false before loading the first document in the viewer to hide the navigation panel from the left side of the viewer containing buttons to view the bookmarks, thumbnails, file attachments and comments of the document. The default value of this property is true. This property is a shortcut for the PdfViewerPreferences.HideWindowUI.

public bool ShowNavigationPanel { get; set; }

Public Property ShowNavigationPanel As Boolean

public:
property bool ShowNavigationPanel {
	bool get ();
	void set (bool value);
}