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| <html><head><meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"><title>Writing Attribute</title><meta name="generator" content="DocBook XSL Stylesheets V1.48"><link rel="home" href="index.html" title="Libxml Tutorial"><link rel="up" href="index.html" title="Libxml Tutorial"><link rel="previous" href="ar01s05.html" title="Writing element content"><link rel="next" href="ar01s07.html" title="Retrieving Attributes"></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">Writing Attribute</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ar01s05.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="ar01s07.html">Next</a></td></tr></table><hr></div><div class="sect1"><div class="titlepage"><div><h2 class="title" style="clear: both"><a name="xmltutorialwritingattribute"></a>Writing Attribute</h2></div></div><p>Writing an attribute is similar to writing text to a new element. In |
| this case, we'll add a reference URI to our |
| document. Full code:<a href="apd.html" title="D. Code for Add Attribute Example">Appendix D</a>.</p><p> |
| A <tt class="sgmltag-element">reference</tt> is a child of the <tt class="sgmltag-element">story</tt> |
| element, so finding the place to put our new element and attribute is |
| simple. As soon as we do the error-checking test in our |
| <tt>parseDoc</tt>, we are in the right spot to add our |
| element. But before we do that, we need to make a declaration using a |
| datatype we have not seen yet: |
| <pre class="programlisting"> |
| xmlAttrPtr newattr; |
| </pre> |
| We also need an extra xmlNodePtr: |
| <pre class="programlisting"> |
| xmlNodePtr newnode; |
| </pre> |
| </p><p> |
| The rest of <tt>parseDoc</tt> is the same as before until we |
| check to see if our root element is <tt class="sgmltag-element">story</tt>. If it is, |
| then we know we are at the right spot to add our element: |
| |
| <pre class="programlisting"> |
| <a name="addreferencenode"></a><img src="images/callouts/1.png" alt="1" border="0"> newnode = xmlNewTextChild (cur, NULL, "reference", NULL); |
| <a name="addattributenode"></a><img src="images/callouts/2.png" alt="2" border="0"> newattr = xmlNewProp (newnode, "uri", uri); |
| </pre> |
| <div class="calloutlist"><table border="0" summary="Callout list"><tr><td width="5%" valign="top" align="left"><a href="#addreferencenode"><img src="images/callouts/1.png" alt="1" border="0"></a> </td><td valign="top" align="left"><p>First we add a new node at the location of the current node |
| pointer, <tt>cur.</tt> using the <a href="http://xmlsoft.org/html/libxml-tree.html#XMLNEWTEXTCHILD" target="_top">xmlNewTextChild</a> function.</p></td></tr></table></div> |
| </p><p>Once the node is added, the file is written to disk just as in the |
| previous example in which we added an element with text content.</p></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ar01s05.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="ar01s07.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Writing element content </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Retrieving Attributes</td></tr></table></div></body></html> |