Question

Possible Duplicate:
Why are “control” characters illegal in XML?
Saving an escape character 0x1b in an XML file

This throws an ArgumentException:

    var c = '\x1A';

    var xml = new XDocument(
                new XDeclaration("1.0", "utf-8", null),
                new XElement("test", new XCData(c.ToString()))
            );

    var foo = xml.ToString(); // ArgumentException

Why is .Net throwing this exception? I’m wrapping the illegal character in CDATA, so I would have thought that illegal characters would be handled for me. This is also the case for a bunch of other characters (e.g. 0x1B, 0x1C, 0x1E, 0x1E, 0x1F).

How do you work around this problem?

Answer 1

I don’t think SecurityElement.Escape will work because \x1A is a control code — there’s no valid xml entity to substitute.

See this list of valid XML characters for a bit more detail.