Re: [xml] inconsistent behavior by "xmlChildElementCount()"

[JerryWRice <JerryWRice fabnexus com>]

Bjoem,

      You must be psychic, as I was in fact using 
"xmlTextReaderCurrentNode()" to get the current node from the reader 
(prior to invoking "xmlChildElementCount()").  I understand your 
explanation, and upon changing my code to invoke 
"xmlTextReaderExpand()", I now receive the correct child count.
      Do you have a recommendation for a comprehensive tutorial type 
document for libxml2?  The online HTML help is good, but the examples 
seem rather simple and sparse.

Thanks,

Jerry W. Rice

On 08/28/2010 01:42 PM, Bjoern Hoehrmann wrote:
> * JerryWRice wrote:
>    
> > My program places this XML document into a zero-terminated char text
> > buffer and creates a reader for it using "xmlReaderForDoc()".  Then I
> > perform a series of "xmlTextReaderRead()" calls to advance my current
> > node to element "<params>" on line 3.  I've confirmed I'm at the opening
> > "<params>" node by using function "xmlTextReadName()" to verify.  While
> > positioned at node "<params>", I call function "xmlChildElementCount()"
> > and expect to get a child element count of "4" (there are four "<param>"
> > sub-element nodes), but instead receive return count value of "3".
> >      
> There is at least one step missing here since xmlTextReaderRead is part
> of the reader interface while xmlChildElementCount is part of the tree
> interface; you would need an xmlNodePtr for xmlChildElementCount but the
> reader usually does not give you one. What are you using exactly to get
> a xmlNodePtr? (In general, it would be much easier to help you with this
> problem had you posted a minimal program to reproduce it.)
>
> xmlChildElementCount simply iterates over the children of an element and
> increments a counter for every element child, the only reason this would
> give you a wrong number is when there is in fact no child element there,
> which may well be the case if you have not read the children yet. If you
> are using `xmlTextReaderCurrentNode` to get the xmlNodePtr then you've
> misread its documentation and may be looking for `xmlTextReaderExpand`.
>