iterator_to_array()

(PHP 5 >= 5.1.0, PHP 7)

将迭代器中的元素拷贝到数组

说明

将迭代器中的元素拷贝到数组。

参数

被拷贝的迭代器。

是否使用迭代器元素键作为索引。

返回值

一个数组，包含迭代器中的元素。

更新日志

范例

iterator_to_array() example

以上例程会输出：

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"
}

To generate an deep array from nested iterators:

I use it to test an iterator: https://gist.github.com/jm42/cb328106f393eeb28751

Using the boolean param :

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"
)

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"
)

Generator approach
function scandir_deep($dir)
{
 foreach (scandir($dir) as $key => $value)
  if (in_array($value, [".",".."]))
   continue;
  else if (is_dir($dir . DIRECTORY_SEPARATOR . $value))
   yield $value => scandir_deep($dir . DIRECTORY_SEPARATOR . $value);
  else
   yield $value;
}

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.

The use_keys parameter was added in one of the 5.2.x releases; it defaults to TRUE. This matches the behavior in PHP 5.1.6, which lacks this parameter.

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