(PHP 5 >= 5.1.0, PHP 7, PHP 8)
iterator_to_array — Copy the iterator into an array
Parametersiterator
The iterator being copied.
preserve_keys
Whether to use the iterator element keys as index.
If a key is an array or object, a warning will be generated. null keys will be converted to an empty string, float keys will be truncated to their int counterpart, resource keys will generate a warning and be converted to their resource ID, and bool keys will be converted to integers.
Note:
If this parameter is not set or set to
true, duplicate keys will be overwritten. The last value with a given key will be in the returned array. Set this parameter tofalseto get all the values in any case.
An array containing the elements of the iterator.
Example #1 iterator_to_array() example
<?php
$iterator = new ArrayIterator(array('recipe'=>'pancakes', 'egg', 'milk', 'flour'));
var_dump(iterator_to_array($iterator, true));
var_dump(iterator_to_array($iterator, false));
?>
The above example will output:
array(4) {
["recipe"]=>
string(8) "pancakes"
[0]=>
string(3) "egg"
[1]=>
string(4) "milk"
[2]=>
string(5) "flour"
}
array(4) {
[0]=>
string(8) "pancakes"
[1]=>
string(3) "egg"
[2]=>
string(4) "milk"
[3]=>
string(5) "flour"
} wizzard351 at yahoo dot com ¶
3 years ago
One important thing to remember is that in iterator can be infinite. Not all iterators necessarily end. If iterator_to_array is used on such an iterator, it will exhaust the available memory, and throw a fatal error.
For example, consider the following code:
<?phpfunction fibonacci(): Generator
{
yield $a = 1;
yield $b = 2;start:
yield $c = $a + $b;
$a = $b;
$b = $c;
goto start;
}$fibonacciSequence = fibonacci();
iterator_to_array($fibonacciSequence);?>
Since <?php fibonacci(); ?> generates an infinite fibonacci sequence, which is valid, since it is actually an infinite sequence, then attempting to convert it to an array will fail. jerome at yazo dot net ¶
16 years ago
Using the boolean param :
<?php
$first
= new ArrayIterator( array('k1' => 'a' , 'k2' => 'b', 'k3' => 'c', 'k4' => 'd') );
$second = new ArrayIterator( array( 'k1' => 'X', 'k2' => 'Y', 'Z' ) ); $combinedIterator= new AppendIterator();
$combinedIterator->append( $first );
$combinedIterator->append( $second ); var_dump( iterator_to_array($combinedIterator, false) ); ?>
will output :
array(7) (
[0]=>
string(1) "a"
[1]=>
string(1) "b"
[2]=>
string(1) "c"
[3]=>
string(1) "d"
[4]=>
string(1) "X"
[5]=>
string(1) "Y"
[6]=>
string(1) "Z"
)
<?php
var_dump
( iterator_to_array($combinedIterator, true) ); ?>
will output (since keys would merge) :
array(5) (
["k1"]=>
string(1) "X"
["k2"]=>
string(1) "Y"
["k3"]=>
string(1) "c"
["k4"]=>
string(1) "d"
[0]=>
string(1) "Z"
) joksnet at gmail dot com ¶
10 years ago
To generate an deep array from nested iterators:
<?php
function iterator_to_array_deep(\Traversable $iterator, $use_keys = true) {
$array = array();
foreach ($iterator as $key => $value) {
if ($value instanceof \Iterator) {
$value = iterator_to_array_deep($value, $use_keys);
}
if ($use_keys) {
$array[$key] = $value;
} else {
$array[] = $value;
}
}
return $array;
}
?>
I use it to test an iterator: https://gist.github.com/jm42/cb328106f393eeb28751 Harry Willis ¶
10 years ago
When using iterator_to_array() on an SplObjectStorage object, it's advisable to set $use_keys to false.
The resulting array is identical, since the iterator keys produced by SplObjectStorage::key() are always integers from 0 to (COUNT-1). Passing $use_keys=false cuts out the unnecessary calls to SplObjectStorage::key(), giving a slight performance advantage.
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4