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  1. <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Writing element content</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="ar01s05.html" title="Using XPath to Retrieve Element Content"><link rel="next" href="ar01s07.html" title="Writing Attribute"></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 element content</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" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="xmltutorialwritingcontent"></a>Writing element content</h2></div></div><div></div></div><p><a class="indexterm" name="id2586968"></a>
  2. Writing element content uses many of the same steps we used above
  3. &#8212; parsing the document and walking the tree. We parse the document,
  4. then traverse the tree to find the place we want to insert our element. For
  5. this example, we want to again find the "storyinfo" element and
  6. this time insert a keyword. Then we'll write the file to disk. Full code:
  7. <a href="ape.html" title="E. Code for Add Keyword Example">Appendix E, <i>Code for Add Keyword Example</i></a></p><p>
  8. The main difference in this example is in
  9. <tt class="function">parseStory</tt>:
  10. </p><pre class="programlisting">
  11. void
  12. parseStory (xmlDocPtr doc, xmlNodePtr cur, char *keyword) {
  13. <a name="addkeyword"></a><img src="images/callouts/1.png" alt="1" border="0"> xmlNewTextChild (cur, NULL, "keyword", keyword);
  14. return;
  15. }
  16. </pre><p>
  17. </p><div class="calloutlist"><table border="0" summary="Callout list"><tr><td width="5%" valign="top" align="left"><a href="#addkeyword"><img src="images/callouts/1.png" alt="1" border="0"></a> </td><td valign="top" align="left"><p>The <tt class="function"><a href="http://xmlsoft.org/html/libxml-tree.html#XMLNEWTEXTCHILD" target="_top">xmlNewTextChild</a></tt>
  18. function adds a new child element at the
  19. current node pointer's location in the
  20. tree, specified by <tt class="varname">cur</tt>.</p></td></tr></table></div><p>
  21. </p><p>
  22. <a class="indexterm" name="id2587052"></a>
  23. Once the node has been added, we would like to write the document to
  24. file. Is you want the element to have a namespace, you can add it here as
  25. well. In our case, the namespace is NULL.
  26. </p><pre class="programlisting">
  27. xmlSaveFormatFile (docname, doc, 1);
  28. </pre><p>
  29. The first parameter is the name of the file to be written. You'll notice
  30. it is the same as the file we just read. In this case, we just write over
  31. the old file. The second parameter is a pointer to the xmlDoc
  32. structure. Setting the third parameter equal to one ensures indenting on output.
  33. </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">Using XPath to Retrieve Element Content </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Writing Attribute</td></tr></table></div></body></html>