Hi,
I am new to the libxml++(1.0) and trying to walk through the examples.
For the dom_xpath example, I tried to do a dynamic_cast for the nodes contained in the NodeSet returned by the Node find method. But it always fails. Is there anything I am doing wrong?
Thanks,
Jin
=======================
// -*- C++ -*-
/* main.cc
*
* Copyright (C) 2002 The libxml++ development team
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <libxml++/libxml++.h>
#include <iostream>
void xpath_test(const xmlpp::Node* node, const std::string& xpath)
{
std::cout << std::endl; //Separate tests by an empty line.
std::cout << "searching with xpath '" << xpath << "' in root node: " << std::endl;
xmlpp::NodeSet set = node->find(xpath);
std::cout << set.size() << " nodes have been found:" << std::endl;
//Print the structural paths:
for(xmlpp::NodeSet::iterator i = set.begin(); i != set.end(); ++i)
{
xmlpp::Element* eNode = dynamic_cast<xmlpp::Element*> (*i);//<====================
std::cout << " " << (*i)->get_path() << " " << (*i)->get_name()<<std::endl;
if (eNode)
std::cout << "Element name:" << eNode->get_name() << std::endl;// <======This line never get printed.
}
}
int main(int argc, char* argv[])
{
std::string filepath;
if(argc > 1 )
filepath = argv[1]; //Allow the user to specify a different XML file to parse.
else
filepath = "example.xml";
try
{
xmlpp::DomParser parser(filepath);
if(parser)
{
const xmlpp::Node* root = parser.get_document()->get_root_node(); //deleted by DomParser.
if(root)
{
// Find all sections, no matter where:
xpath_test(root, "//section");
// Find the title node (if there is one):
xpath_test(root, "title");
std::cout << std::endl;
// And finally test whether intra-document links are well-formed.
// To be well-formed, the 'linkend' attribute must refer to
// an element in terms of its 'id'.
//
// Find out whether there are linkend attributes that don't have
// corresponding 'id's
std::cout << "searching for unresolved internal references "
<< "(see docbook manual):" << std::endl;
xpath_test(root, "//xref/@linkend");
}
}
}
catch(const std::exception& ex)
{
std::cout << "Exception caught: " << ex.what() << std::endl;
}
return 0;
}
========================
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
"http://www.oasis-open.org/docbook/xml/4.0/docbookx.dtd">
<article>
<title>An Article</title>
<section id="section1">
<title>A section</title>
<para>This is a paragraph.</para>
</section>
<section id="section2">
<title>Another section</title>
<section id="section3">
<title>A sub-section</title>
<para>This paragraph refers to <xref linkend="section1"/>,
<xref linkend="section2"/>, and <xref linkend="section4"/>.</para>
</section>
</section>
</article>