Are line breaks in XML attribute values allowed?

Question

I realise that it's not elegant or desired, but is it allowed (in well-formed XML) for an attribute value in an XML element to span multiple lines?

e.g.

<some-xml-element value="this value goes over.... multiple lines!" /> 

Yeah I realise there's better ways of writing that. I would personally write it like:

<some-xml-element> <value>this value goes over... multiple lines!</value> </some-xml-element> 

or:

<some-xml-element value="this value goes over....&#13;&#10;" /> 

But we have our own XML parser and I'd like to know whether the first example is allowed in well-formed XML.

Answer 1

http://www.w3.org/TR/REC-xml/#NT-AttValue

Seems to say everything except <, &, and your delimiter (' or ") are OK. So newline should be, too.

Answer 2

It is allowed, however according to W3C recommendation your XML parser should normalize the all whitespace characters to space (0x20) - so the output of your examples will differ (you should have new line on the output for "
", but only space in the first case).

http://www.w3.org/TR/1998/REC-xml-19980210#AVNormalize