private void ReloadDocument()
{
	var navigationPane = this.pdfViewerNavigationPane;
	var navigationPaneTreeView = navigationPane.FindChildByType<RadTreeView>();
	if (navigationPaneTreeView != null)
	{
		object itemStorage = typeof(RadTreeView)
			.GetProperty("ItemStorage", BindingFlags.Instance | BindingFlags.NonPublic)
			.GetValue(navigationPaneTreeView);
		MethodInfo itemStorageClearMethod = itemStorage.GetType().GetMethod("Clear", BindingFlags.Instance | BindingFlags.NonPublic);
		itemStorageClearMethod.Invoke(itemStorage, null);		
	}
	
	this.DocumentSource = theNewDocumentSource;
}

this.pdfViewer.Document.AcroForm.FlattenFormFields();

using (Stream output = File.OpenWrite("Exported.pdf"))
{
	this.pdfViewer.Save(output);
}

this.pdfViewer.Document.AcroForm.FlattenFormFields();

using (Stream output = File.OpenWrite("Exported.pdf"))
{
	PdfFormatProvider provider = new PdfFormatProvider();
	provider.Export(this.pdfViewer.Document, output);
}