MDT 2004 John Fleck | 4c3bb7d | 2004-08-25 02:51:27 +0000 | [diff] [blame^] | 1 | <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Writing Attribute</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="ar01s06.html" title="Writing element content"><link rel="next" href="ar01s08.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="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" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="xmltutorialwritingattribute"></a>Writing Attribute</h2></div></div><div></div></div><p><a class="indexterm" name="id2587093"></a> |
MDT 2003 John Fleck | 63f3a47 | 2003-07-24 21:48:30 +0000 | [diff] [blame] | 2 | Writing an attribute is similar to writing text to a new element. In |
| 3 | this case, we'll add a reference <span class="acronym">URI</span> to our |
| 4 | document. Full code:<a href="apf.html" title="F. Code for Add Attribute Example">Appendix F, <i>Code for Add Attribute Example</i></a>.</p><p> |
| 5 | A <tt class="sgmltag-element">reference</tt> is a child of the <tt class="sgmltag-element">story</tt> |
| 6 | element, so finding the place to put our new element and attribute is |
| 7 | simple. As soon as we do the error-checking test in our |
| 8 | <tt class="function">parseDoc</tt>, we are in the right spot to add our |
| 9 | element. But before we do that, we need to make a declaration using a |
| 10 | data type we have not seen yet: |
MST 2003 John Fleck | 731967e | 2003-01-27 00:39:50 +0000 | [diff] [blame] | 11 | </p><pre class="programlisting"> |
MDT 2003 John Fleck | 63f3a47 | 2003-07-24 21:48:30 +0000 | [diff] [blame] | 12 | xmlAttrPtr newattr; |
MST 2003 John Fleck | 731967e | 2003-01-27 00:39:50 +0000 | [diff] [blame] | 13 | </pre><p> |
MDT 2003 John Fleck | 63f3a47 | 2003-07-24 21:48:30 +0000 | [diff] [blame] | 14 | We also need an extra xmlNodePtr: |
| 15 | </p><pre class="programlisting"> |
| 16 | xmlNodePtr newnode; |
| 17 | </pre><p> |
| 18 | </p><p> |
| 19 | The rest of <tt class="function">parseDoc</tt> is the same as before until we |
| 20 | check to see if our root element is <tt class="sgmltag-element">story</tt>. If it is, |
| 21 | then we know we are at the right spot to add our element: |
| 22 | |
| 23 | </p><pre class="programlisting"> |
| 24 | <a name="addreferencenode"></a><img src="images/callouts/1.png" alt="1" border="0"> newnode = xmlNewTextChild (cur, NULL, "reference", NULL); |
| 25 | <a name="addattributenode"></a><img src="images/callouts/2.png" alt="2" border="0"> newattr = xmlNewProp (newnode, "uri", uri); |
| 26 | </pre><p> |
| 27 | </p><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 |
| 28 | pointer, <tt class="varname">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> |
| 29 | </p><p>Once the node is added, the file is written to disk just as in the |
| 30 | 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="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 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> |