Compress and secure XML?

[Santastp]

Hi!

This is a situation who can happen often and I would like to know if
something
exist.

I try to create an application who use XML as a native database. The problem
is
that I don't want that the user can play in the XML. I would like to
compress the file
and encrypt so to block the user. The goal is to have a class that can read
directly in
the file (compressed and encrypted) as a normal XML document and can not be
read
in an editor.

I know that it's possible to do that seperatly but the performance is
touched.
Sometime it has company or people who has done it as super performant API.

Suggestion?

Something like:

XmlDocument xmlDocument = new XmlDocument();
xmlDocument.Load(file);

XmlCompressedDocument xmlfile = new XmlCompressedDocument();
xmlfile.Load(xmlDocument);
xmlfile.Compress(xmlDocument);
xmlfile.Encrypt(xmlfile);
xmlfile.Save(path);

Thanks

Stephane