Add an option to save and/or email document. It is especially useful if a file stream is loaded into the viewer.

Currently, the following approach can be used: 
private Stream GetPdfStream()
{

Type documentType = this.radPdfViewer1.PdfViewerElement.Document.GetType();

FieldInfo internalDocumentField = documentType.GetField("internalDocument", BindingFlags.NonPublic | BindingFlags.Instance);

object internalDocumentValue = internalDocumentField.GetValue(this.radPdfViewer1.PdfViewerElement.Document);

FieldInfo formatProviderField = internalDocumentValue.GetType().GetField("formatProvider", BindingFlags.NonPublic | BindingFlags.Instance);

PdfFormatProvider formatProvder = formatProviderField.GetValue(internalDocumentValue) as PdfFormatProvider;

FieldInfo field = formatProvder.GetType().GetField("stream", BindingFlags.NonPublic | BindingFlags.GetField | BindingFlags.Instance);

Stream stream = field.GetValue(formatProvder) as Stream;
return stream;
}