iterator

ENTITY
Interface for external iterators or objects that can be iterated themselves internally.
ENTITY
Iterator
extends
Traversable
ENTITY
Predefined iterators
PHP already provides a number of iterators for many day-to-day tasks. See SPL iterators for a list.
ENTITY
Basic usage
This example demonstrates in which order methods are called when using ENTITY with an iterator.
<?php
class myIterator implements Iterator {
    private $position = 0;
    private $array = array(
        "firstelement",
        "secondelement",
        "lastelement",
    );  
    public function __construct() {
        $this->position = 0;
    }
    public function rewind(): void {
        var_dump(__METHOD__);
        $this->position = 0;
    }
    #[\ReturnTypeWillChange]
    public function current() {
        var_dump(__METHOD__);
        return $this->array[$this->position];
    }
    #[\ReturnTypeWillChange]
    public function key() {
        var_dump(__METHOD__);
        return $this->position;
    }
    public function next(): void {
        var_dump(__METHOD__);
        ++$this->position;
    }
    public function valid(): bool {
        var_dump(__METHOD__);
        return isset($this->array[$this->position]);
    }
}
$it = new myIterator;
foreach($it as $key => $value) {
    var_dump($key, $value);
    echo "\n";
}
?>
    
ENTITY
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"
ENTITY
See also object iteration.
ENTITY ENTITY ENTITY ENTITY ENTITY