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current: 2
key: 1
1: 2
next: 3
current: 3
valid: 1
current: 3
key: 2
2: 3
next:
current:
valid:
</pre></div>
   </pre></div>

  </div>

  <p class="para">
   You can also define your class so that it doesn&#039;t have to define
   all the <var class="varname">Iterator</var> functions by simply implementing
   the PHP 5 <var class="varname">IteratorAggregate</var> interface.
  </p>

  <div class="example">
   <p><b>Example #3 Object Iteration implementing IteratorAggregate</b></p>
   <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #007700">class&nbsp;</span><span style="color: #0000BB">MyCollection&nbsp;</span><span style="color: #007700">implements&nbsp;</span><span style="color: #0000BB">IteratorAggregate<br /></span><span style="color: #007700">{<br />&nbsp;&nbsp;&nbsp;&nbsp;private&nbsp;</span><span style="color: #0000BB">$items&nbsp;</span><span style="color: #007700">=&nbsp;array();<br />&nbsp;&nbsp;&nbsp;&nbsp;private&nbsp;</span><span style="color: #0000BB">$count&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">0</span><span style="color: #007700">;<br /><br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #FF8000">//&nbsp;Required&nbsp;definition&nbsp;of&nbsp;interface&nbsp;IteratorAggregate<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #007700">public&nbsp;function&nbsp;</span><span style="color: #0000BB">getIterator</span><span style="color: #007700">()&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;return&nbsp;new&nbsp;</span><span style="color: #0000BB">MyIterator</span><span style="color: #007700">(</span><span style="color: #0000BB">$this</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">items</span><span style="color: #007700">);<br />&nbsp;&nbsp;&nbsp;&nbsp;}<br /><br />&nbsp;&nbsp;&nbsp;&nbsp;public&nbsp;function&nbsp;</span><span style="color: #0000BB">add</span><span style="color: #007700">(</span><span style="color: #0000BB">$value</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">$this</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">items</span><span style="color: #007700">[</span><span style="color: #0000BB">$this</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">count</span><span style="color: #007700">++]&nbsp;=&nbsp;</span><span style="color: #0000BB">$value</span><span style="color: #007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;}<br />}<br /><br /></span><span style="color: #0000BB">$coll&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">MyCollection</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">$coll</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">add</span><span style="color: #007700">(</span><span style="color: #DD0000">'value&nbsp;1'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$coll</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">add</span><span style="color: #007700">(</span><span style="color: #DD0000">'value&nbsp;2'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$coll</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">add</span><span style="color: #007700">(</span><span style="color: #DD0000">'value&nbsp;3'</span><span style="color: #007700">);<br /><br />foreach&nbsp;(</span><span style="color: #0000BB">$coll&nbsp;</span><span style="color: #007700">as&nbsp;</span><span style="color: #0000BB">$key&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">$val</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"key/value:&nbsp;[$key&nbsp;-&gt;&nbsp;$val]\n\n"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
   </div>

   <div class="example-contents"><p>The above example will output:</p></div>  
   <div class="example-contents"><pre>
<div class="cdata"><pre>
rewinding
current: value 1
valid: 1
current: value 1
key: 0
key/value: [0 -&gt; value 1]

next: value 2
current: value 2
valid: 1
current: value 2
key: 1
key/value: [1 -&gt; value 2]

next: value 3
current: value 3
valid: 1
current: value 3
key: 2
key/value: [2 -&gt; value 3]

next:
current:
valid:
</pre></div>
   </pre></div>

  </div>

  <blockquote><p><b class="note">Note</b>: 
   
    For more examples of iterators, see the
    <a href="ref.spl.html" class="link">SPL Extension</a>.
   <br />
  </p></blockquote> 

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