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 1  <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>D.�Code for XPath Example</title><meta name="generator" content="DocBook XSL Stylesheets V1.61.2"><link rel="home" href="index.html" title="Libxml Tutorial"><link rel="up" href="index.html" title="Libxml Tutorial"><link rel="previous" href="apc.html" title="C.�Code for Keyword Example"><link rel="next" href="ape.html" title="E.�Code for Add Keyword Example"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">D.�Code for XPath Example</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="apc.html">Prev</a>�</td><th width="60%" align="center">�</th><td width="20%" align="right">�<a accesskey="n" href="ape.html">Next</a></td></tr></table><hr></div><div class="appendix" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="xpathappendix"></a>D.�Code for XPath Example</h2></div></div><div></div></div><p>
 2        </p><pre class="programlisting">
 3  #include &lt;libxml/parser.h&gt;
 4  #include &lt;libxml/xpath.h&gt;
 5  
 6  xmlDocPtr
 7  getdoc (char *docname) {
 8  	xmlDocPtr doc;
 9  	doc = xmlParseFile(docname);
10  	
11  	if (doc == NULL ) {
12  		fprintf(stderr,"Document not parsed successfully. \n");
13  		return NULL;
14  	}
15  
16  	return doc;
17  }
18  
19  xmlXPathObjectPtr
20  getnodeset (xmlDocPtr doc, xmlChar *xpath){
21  	
22  	xmlXPathContextPtr context;
23  	xmlXPathObjectPtr result;
24  
25  	context = xmlXPathNewContext(doc);
26  	if (context == NULL) {
27  		printf("Error in xmlXPathNewContext\n");
28  		return NULL;
29  	}
30  	result = xmlXPathEvalExpression(xpath, context);
31  	xmlXPathFreeContext(context);
32  	if (result == NULL) {
33  		printf("Error in xmlXPathEvalExpression\n");
34  		return NULL;
35  	}
36  	if(xmlXPathNodeSetIsEmpty(result-&gt;nodesetval)){
37  		xmlXPathFreeObject(result);
38                  printf("No result\n");
39  		return NULL;
40  	}
41  	return result;
42  }
43  int
44  main(int argc, char **argv) {
45  
46  	char *docname;
47  	xmlDocPtr doc;
48  	xmlChar *xpath = (xmlChar*) "//keyword";
49  	xmlNodeSetPtr nodeset;
50  	xmlXPathObjectPtr result;
51  	int i;
52  	xmlChar *keyword;
53  		
54  	if (argc &lt;= 1) {
55  		printf("Usage: %s docname\n", argv[0]);
56  		return(0);
57  	}
58  
59  	docname = argv[1];
60  	doc = getdoc(docname);
61  	result = getnodeset (doc, xpath);
62  	if (result) {
63  		nodeset = result-&gt;nodesetval;
64  		for (i=0; i &lt; nodeset-&gt;nodeNr; i++) {
65  			keyword = xmlNodeListGetString(doc, nodeset-&gt;nodeTab[i]-&gt;xmlChildrenNode, 1);
66  		printf("keyword: %s\n", keyword);
67  		xmlFree(keyword);
68  		}
69  		xmlXPathFreeObject (result);
70  	}
71  	xmlFreeDoc(doc);
72  	xmlCleanupParser();
73  	return (1);
74  }
75  </pre><p>
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