King Nak wrote:
Hi!I'm a novice to xalan and have a problem: I've got a big XML file representing a product calalogue. here an example excerpt: <catalogue> <chapter> <!-- some more hierarchy --> <product uid="12345"> <article-set> <article uid="87"><!-- omitted --></article> <article uid="88"><!-- omitted --></article> <article uid="89"><!-- omitted --></article> </article-set> </product> <product uid="7680"> <!-- a.s.o --> </product> </chapter> </catalogue> In my programm I have to process most (or all) of the elements having a uid attribute one by one, no matter what kind of element they are. I could use "//[EMAIL PROTECTED] = myuid]" everytime, but for performance issues, I want to cache the list of elements having a uid. so I use "//[EMAIL PROTECTED]" to get these elements. this xpath gives me a XNodeSetBase. in further expressions, I have to select a specific element in this nodeset by its uid. in Xalan-C API reference, I found XObjectPtr::rtree() returning a const XalanDocumentTreeFragment &. This class is a subclass of XalanNode and could be used as a context for the XPathEvaluator (the const can be casted away, see http://marc.theaimsgroup.com/?l=xalan-c-users&m=108145747222899&w=2
I don't know why you would want to cast a node-set to a result tree fragment. You certainly wouldn't want to use this as the context for another evaluation, since it would yield no results.
here ) but when I'm using this, a NULL-pointer is accessed. That's because XObjectResultTreeFragProxyBase::getOwnerDocument() always returns 0, so I can't get the nodeset's owner document... is there any way to store a nodelist returned by an XPath to be used as the context on another XPath?
Copy the nodes from the nodeset into your own container. You can use std::vector<XalanNode*>, or Xalan-C's NodeRefList class:
NodeRefList cachedNodes(xobj->nodeset()); Dave
