Who said that XmlDocument's XPathNavigator is not editable?

I've checked today's toy in cvs; SubtreeXmlReader.cs. It is used to implement XmlReader.ReadSubtree().

After creating it, I felt sorry, since it is not interesting one. So today I made another subtree reader; XPathNavigatorReader.cs (for XPathNavigator.ReadSubtree()). It in fact used to be in cvs for a while (and moreover I made it more than 1 year ago), but it did not behave as a fragment reader.

Well, though they are based on 2.0 bits, they could be easily modified to be usable on 1.x. Once such modification is done, you could replace XmlReader.ReadSubtree() and XPathNavigator.ReadSubtree() with them for backward compatibility. They are also runnable under MS.NET.

Update [7/31]: The XPathNavigatorReader implementation was so buggy... so please pick the correct implementation up from mono cvs.