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<H3><A NAME="SECTION0015623000000000000000"></A><A NAME="dom-nodelist-objects"></A>
<BR>
13.6.2.3 NodeList Objects
</H3>

<P>
A <tt class="class">NodeList</tt> represents a sequence of nodes.  These objects are
used in two ways in the DOM Core recommendation:  the
<tt class="class">Element</tt> objects provides one as its list of child nodes, and
the <tt class="method">getElementsByTagName()</tt> and
<tt class="method">getElementsByTagNameNS()</tt> methods of <tt class="class">Node</tt> return
objects with this interface to represent query results.

<P>
The DOM Level&nbsp;2 recommendation defines one method and one attribute
for these objects:

<P>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><tt id='l2h-4385' xml:id='l2h-4385' class="method">item</tt></b>(</nobr></td>
  <td><var>i</var>)</td></tr></table></dt>
<dd>
  Return the <var>i</var>'th item from the sequence, if there is one, or
  <code>None</code>.  The index <var>i</var> is not allowed to be less then zero
  or greater than or equal to the length of the sequence.
</dl>

<P>
<dl><dt><b><tt id='l2h-4386' xml:id='l2h-4386' class="member">length</tt></b></dt>
<dd>
  The number of nodes in the sequence.
</dl>

<P>
In addition, the Python DOM interface requires that some additional
support is provided to allow <tt class="class">NodeList</tt> objects to be used as
Python sequences.  All <tt class="class">NodeList</tt> implementations must include
support for <tt class="method">__len__()</tt> and <tt class="method">__getitem__()</tt>; this allows
iteration over the <tt class="class">NodeList</tt> in <tt class="keyword">for</tt> statements and
proper support for the <tt class="function">len()</tt> built-in function.

<P>
If a DOM implementation supports modification of the document, the
<tt class="class">NodeList</tt> implementation must also support the
<tt class="method">__setitem__()</tt> and <tt class="method">__delitem__()</tt> methods.

<P>

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<span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span>
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