(PHP 5 >= 5.0.0)
Interface for external iterators or objects that can be iterated themselves internally.
PHP already provides a number of iterators for many day to day tasks. See SPL iterators for a list.
Example #1 Basic usage
This example demonstrates in which order methods are called when using foreach with an iterator.
<?php
class myIterator implements Iterator {
private $position = 0;
private $array = array(
"firstelement",
"secondelement",
"lastelement",
);
public function __construct() {
$this->position = 0;
}
function rewind() {
var_dump(__METHOD__);
$this->position = 0;
}
function current() {
var_dump(__METHOD__);
return $this->array[$this->position];
}
function key() {
var_dump(__METHOD__);
return $this->position;
}
function next() {
var_dump(__METHOD__);
++$this->position;
}
function valid() {
var_dump(__METHOD__);
return isset($this->array[$this->position]);
}
}
$it = new myIterator;
foreach($it as $key => $value) {
var_dump($key, $value);
echo "\n";
}
?>
Il precedente esempio visualizzerà qualcosa simile a:
string(18) "myIterator::rewind" string(17) "myIterator::valid" string(19) "myIterator::current" string(15) "myIterator::key" int(0) string(12) "firstelement" string(16) "myIterator::next" string(17) "myIterator::valid" string(19) "myIterator::current" string(15) "myIterator::key" int(1) string(13) "secondelement" string(16) "myIterator::next" string(17) "myIterator::valid" string(19) "myIterator::current" string(15) "myIterator::key" int(2) string(11) "lastelement" string(16) "myIterator::next" string(17) "myIterator::valid"