RecursiveIteratorIterator::__construct()

(PHP 5 >= 5.1.3, PHP 7)

Construct a RecursiveIteratorIterator

说明

publicRecursiveIteratorIterator::__construct(Traversable$iterator[,int $mode= RecursiveIteratorIterator::LEAVES_ONLY[,int $flags= 0]])

Creates a RecursiveIteratorIterator from a RecursiveIterator.

参数

$iterator

The iterator being constructed from. Either a RecursiveIterator or IteratorAggregate.

$mode

Optional mode. Possible values are

• RecursiveIteratorIterator::LEAVES_ONLY- The default. Lists only leaves in iteration.
• RecursiveIteratorIterator::SELF_FIRST- Lists leaves and parents in iteration with parents coming first.
• RecursiveIteratorIterator::CHILD_FIRST- Lists leaves and parents in iteration with leaves coming first.

$flags

Optional flag. Possible values are RecursiveIteratorIterator::CATCH_GET_CHILD which will then ignore exceptions thrown in calls to RecursiveIteratorIterator::getChildren().

返回值

没有返回值。

范例

Iterating a RecursiveIteratorIterator

<?php
$array = array(
    array(
        array(
            array(
                'leaf-0-0-0-0',
                'leaf-0-0-0-1'
            ),
            'leaf-0-0-0'
        ),
        array(
            array(
                'leaf-0-1-0-0',
                'leaf-0-1-0-1'
            ),
            'leaf-0-1-0'
        ),
        'leaf-0-0'
    )
);
$iterator = new RecursiveIteratorIterator(
    new RecursiveArrayIterator($array),
    $mode
);
foreach ($iterator as $key => $leaf) {
    echo "$key => $leaf", PHP_EOL;
}
?>

Output with $mode = RecursiveIteratorIterator::LEAVES_ONLY

0 => leaf-0-0-0-0
1 => leaf-0-0-0-1
0 => leaf-0-0-0
0 => leaf-0-1-0-0
1 => leaf-0-1-0-1
0 => leaf-0-1-0
0 => leaf-0-0

Output with $mode = RecursiveIteratorIterator::SELF_FIRST

0 => Array
0 => Array
0 => Array
0 => leaf-0-0-0-0
1 => leaf-0-0-0-1
1 => leaf-0-0-0
1 => Array
0 => Array
0 => leaf-0-1-0-0
1 => leaf-0-1-0-1
1 => leaf-0-1-0
2 => leaf-0-0

Output with $mode = RecursiveIteratorIterator::CHILD_FIRST

0 => leaf-0-0-0-0
1 => leaf-0-0-0-1
0 => Array
1 => leaf-0-0-0
0 => Array
0 => leaf-0-1-0-0
1 => leaf-0-1-0-1
0 => Array
1 => leaf-0-1-0
1 => Array
2 => leaf-0-0
0 => Array

Note: the missing documentation of the argument list for this constructor is currently as follows (according to source code).
Param iter: see RecursiveIterator
Param mode:
- LEAVES_ONLY = (default) only iterate leaves
- SELF_FIRST = iterate parents prior to children
- CHILD_FIRST = iterate children prior to parents
Param flags:
- CATCH_GET_CHILD = ignore exceptions in getChildren() call

Note that LEAVES_ONLY, SELF_FIRST and CHILD_FIRST do not work by themselves.
They are class constants so you need to use RecursiveIteratorIterator::LEAVES_ONLY, etc.