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2<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Retrieving Attributes</title><meta name="generator" content="DocBook XSL Stylesheets V1.50.0"><link rel="home" href="index.html" title="Libxml Tutorial"><link rel="up" href="index.html" title="Libxml Tutorial"><link rel="previous" href="ar01s06.html" title="Writing Attribute"><link rel="next" href="ar01s08.html" title="Encoding Conversion"></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">Retrieving Attributes</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s06.html">Prev</a>�</td><th width="60%" align="center">�</th><td width="20%" align="right">�<a accesskey="n" href="ar01s08.html">Next</a></td></tr></table><hr></div><div class="sect1"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="xmltutorialattribute"></a>Retrieving Attributes</h2></div></div><p>Retrieving the value of an attribute is similar to the previous
3    example in which we retrieved a node's text contents. In this case we'll
4      extract the value of the URI we added in the previous
5      section. Full code: <a href="ape.html" title="E. Code for Retrieving Attribute Value Example">Appendix E</a>.</p><p>
6      The initial steps for this example are similar to the previous ones: parse
7      the doc, find the element you are interested in, then enter a function to
8      carry out the specific task required. In this case, we call
9      <tt>getReference</tt>:
10      <pre class="programlisting">
11void
12getReference (xmlDocPtr doc, xmlNodePtr cur) {
13
14	xmlChar *uri;
15	cur = cur-&gt;xmlChildrenNode;
16	while (cur != NULL) {
17	    if ((!xmlStrcmp(cur-&gt;name, (const xmlChar *)&quot;reference&quot;))) {
18		   <a name="getattributevalue"></a><img src="images/callouts/1.png" alt="1" border="0"> uri = xmlGetProp(cur, &quot;uri&quot;);
19		    printf(&quot;uri: %s\n&quot;, uri);
20		    xmlFree(uri);
21	    }
22	    cur = cur-&gt;next;
23	}
24	return;
25}
26      </pre>
27    
28      </p><div class="calloutlist"><table border="0" summary="Callout list"><tr><td width="5%" valign="top" align="left"><a href="#getattributevalue"><img src="images/callouts/1.png" alt="1" border="0"></a> </td><td valign="top" align="left"><p>
29	    The key function is <tt><a href="http://xmlsoft.org/html/libxml-tree.html#XMLGETPROP" target="_top">xmlGetProp</a></tt>, which returns an
30      <tt>xmlChar</tt> containing the attribute's value. In this case,
31					   we just print it out.
32      </p><div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"><table border="0"><tr><td rowspan="2" align="center" valign="top" width="25"><img src="images/note.png"></td><th>Note</th></tr><tr><td colspan="2" align="left" valign="top"><p>
33	  If you are using a DTD that declares a fixed or
34	  default value for the attribute, this function will retrieve it.
35	</p></td></tr></table></div><p>
36	  </p></td></tr></table></div><p>
37     
38    </p></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ar01s06.html">Prev</a>�</td><td width="20%" align="center"><a accesskey="u" href="index.html">Up</a></td><td width="40%" align="right">�<a accesskey="n" href="ar01s08.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Writing Attribute�</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">�Encoding Conversion</td></tr></table></div></body></html>
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