Re: [xml] query - append DOM tree, identify leaf node

[Lars Oppermann <Lars Oppermann Sun COM>]

Senthil Nathan wrote:
> 1. Suppose if I have a pointer xmlDoc *doc1 to a DOM tree, built using 
> xmlReadFile( ) or xmlParseFile( ) for file1.xml.
>     Is it possible to add another DOM tree to this existing tree?
>     Like, if *doc2 points to another DOM tree of file2.xml, can this be 
> appended to the *doc1.

Have a look at the tree module API documentation

xmlNodePtr xmlDocCopyNode(const xmlNodePtr node,
  xmlDocPtr doc,
  int extended)
http://www.xmlsoft.org/html/libxml-tree.html#xmlDocCopyNode

You can then append the node to its new parent in doc1 with xmlAddChild
http://www.xmlsoft.org/html/libxml-tree.html#xmlAddChild

> 2. Using xmlXPathEvalExpression( ), I could search for a tree structure 
> exists in the DOM tree or not.
>     But how do I find that is the leaf node.
>    
>     <node>
>           <n1>a</n1>
>                 <n11>abc</n11>
>           <n2>b</n2>
>     </node>

With leaf node I assume you mean an element node that has only text or 
attribute children but no other element children. A way of doing this in 
XPath is like this:

//*[count(./*)=0]

Which reads a select all elements E such that the count of element 
children of E is zero.

You can also traverse the tree with the tree api and check whether a 
node has no children of node-type element, but I find using XPath much 
more convenient

HTH
Lars.

--
Sun Microsystems                Lars Oppermann <lars oppermann sun com>
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