"Re: [xml] how to write a xmlAttr with xmlTextWriter?"

[Kasimier Buchcik <kbuchcik 4commerce de>]

Hi,

on 2/10/2004 4:45 PM Daniel Veillard wrote:

> On Tue, Feb 10, 2004 at 04:38:10PM +0100, Kasimier Buchcik wrote:
>
> > Hi,
> >
> > on 2/10/2004 2:23 PM Kasimier Buchcik wrote:
> >
> >
> > > Hi,
> > >
> > > does there exist a function that can serialize the content of a xmlAttr 
> > > (attr->children) to be used with "xmlTextWriterWriteAttribute"? It 
> > > should bear analogy to "xmlAttrSerializeContent" which is used by the 
> > > serialization mechanism internally. If no, did someone already succeded 
> > > in xml-text-writing an xmlAttr?
> >
> >
> > Hmm, I tried the following combination but it does not behave properly:
> >
> > attrVal = xmlNodeListGetString(NULL, attr->children, 0);
> > xmlTextWriterWriteAttribute(writer, attr->name, attrVal);
> >
> > Since "xmlNodeListGetString" and "xmlTextWriterWriteAttribute" both lead 
> > to a "&" to "&" conversion, I get a recursive conversion if cycling 
> > serialization & parsing:
> >
> > "<" --> "&amp;lt;" --> "&amp;amp;lt;" --> etc.
> >
> > Entity references will be mangled by xmlTextWriterWriteAttribute.
> > Is there any chance of adding to "xmlAttrSerializeTxtContent" (called by 
> > "xmlTextWriterWriteAttribute") a heuristic evaluation if a "&" is a 
> > beginning of an entity reference or not? But maby this does not fit in 
> > the big picture. Any other clues?
>
>
>   < in attributes must be escaped. attr->children should be a list
> of text node and attribute references, usually you will just get
> a text node. Apparently the current xmlTextWriter API won't allow
> you to output entities references. That's all I can say. If you
> have just a text node use its content as the value passed to
> xmlTextWriterWriteAttribute(), otherwise if you have an entity reference
> well that would need an API extension I'm afraid.

I see. Hmm, would it be correct to use "xmlNodeListGetString" with 
conjunction with "xmlTextWriterWriteRaw" for the attribute value? When I 
compare "xmlNodeListGetString" with "xmlAttrSerializeTxtContent", the 
latter does some additional text processing (which I'm not able to 
understand by now), so I wonder if "xmlNodeListGetString" chews enough 
to produce a text to be written.


Kasimier