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This iterator allows to unset and modify values and keys while iterating over Arrays and Objects.
When you want to iterate over the same array multiple times you need to instantiate ArrayObject and let it create ArrayIterator instances that refer to it either by using foreach or by calling its getIterator() method manually.
Unsetting all keys of an ArrayItem within foreach will always leave the second key:
<?php
$items = new ArrayObject(range(0, 9));
while (list($k, $v) = each($items)) {
unset($items[$k]);
}
print_r($items);
// ArrayIterator Object
// (
// [storage:ArrayIterator:private] => Array
// (
// [1] => 1
// )
// )
?>
I'm not sure if this is a bug as unsetting keys within foreach is usually a bad idea to begin with (use while instead), but it's something to be aware of.
If you want to make your ArrayIterator support foreach loops with PHP's & operator, such as
<?php
foreach($list as &$item) {
....
}
?>
You will need to pass the array to ArrayIterator by reference:
<?php
new ArrayIterator(&$array);
?>
and to iterate recursively use the (sparsely documented) RecursiveArrayIterator
<?php
$fruits = array(
"apple" => "yummy",
"orange" => "ah ya, nice",
"grape" => "wow, I love it!",
"plum" => "nah, not me"
);
$veg = array("potato" => "chips", "carrot" => "soup");
$grocery = array($fruits, $veg);
$obj = new ArrayObject( $grocery );
$it = new RecursiveIteratorIterator( new RecursiveArrayIterator($grocery));
foreach ($it as $key=>$val)
echo $key.":".$val."\n";
?>
Output
--------
apple:yummy
orange:ah ya, nice
grape:wow, I love it!
plum:nah, not me
potato:chips
carrot:soup
Another fine Iterator from php . You can use it especially when you have to iterate over objects
<?php
$fruits = array(
"apple" => "yummy",
"orange" => "ah ya, nice",
"grape" => "wow, I love it!",
"plum" => "nah, not me"
);
$obj = new ArrayObject( $fruits );
$it = $obj->getIterator();
// How many items are we iterating over?
echo "Iterating over: " . $obj->count() . " values\n";
// Iterate over the values in the ArrayObject:
while( $it->valid() )
{
echo $it->key() . "=" . $it->current() . "\n";
$it->next();
}
// The good thing here is that it can be iterated with foreach loop
foreach ($it as $key=>$val)
echo $key.":".$val."\n";
/* Outputs something like */
Iterating over: 4 values
apple=yummy
orange=ah ya, nice
grape=wow, I love it!
plum=nah, not me
?>
Regards.
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