AppendIterator::valid
Need a callback on an iterated value, but don't have PHP 5.4+? This makes is stupid easy:
<?php
class ArrayCallbackIterator extends ArrayIterator {
private $callback;
public function __construct($value, $callback) {
parent::__construct($value);
$this->callback = $callback;
}
public function current() {
$value = parent::current();
return call_user_func($this->callback, $value);
}
}
?>
You can use it pretty much exactly as the Array Iterator:
<?php
$iterator1 = new ArrayCallbackIterator($valueList, "callback_function");
$iterator2 = new ArrayCallbackIterator($valueList, array($object, "callback_class_method"));
?>
The ArrayIterator class
(PHP 5)
Introduction
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.
Class synopsis
/* Methods */
}Table of Contents
- ArrayIterator::append — Append an element
- ArrayIterator::asort — Sort array by values
- ArrayIterator::__construct — Construct an ArrayIterator
- ArrayIterator::count — Count elements
- ArrayIterator::current — Return current array entry
- ArrayIterator::getArrayCopy — Get array copy
- ArrayIterator::getFlags — Get flags
- ArrayIterator::key — Return current array key
- ArrayIterator::ksort — Sort array by keys
- ArrayIterator::natcasesort — Sort an array naturally, case insensitive
- ArrayIterator::natsort — Sort an array naturally
- ArrayIterator::next — Move to next entry
- ArrayIterator::offsetExists — Check if offset exists
- ArrayIterator::offsetGet — Get value for an offset
- ArrayIterator::offsetSet — Set value for an offset
- ArrayIterator::offsetUnset — Unset value for an offset
- ArrayIterator::rewind — Rewind array back to the start
- ArrayIterator::seek — Seek to position
- ArrayIterator::serialize — Serialize
- ArrayIterator::setFlags — Set behaviour flags
- ArrayIterator::uasort — User defined sort
- ArrayIterator::uksort — User defined sort
- ArrayIterator::unserialize — Unserialize
- ArrayIterator::valid — Check whether array contains more entries
add a note
User Contributed Notes
ArrayIterator - [4 notes]
Relakuyae ¶
1 year ago
Sean Burlington ¶
4 years ago
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
Venelin Vulkov ¶
4 years ago
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.
foobuilder at gmail dot com ¶
2 years ago
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.