RecursiveIteratorIterator::__construct

(PHP 5 >= 5.1.3, PHP 7)

RecursiveIteratorIterator::__construct — Construct a RecursiveIteratorIterator

说明

public RecursiveIteratorIterator::__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

Example #1 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

User Contributed Notes

Tom 06-Jan-2011 10:13


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

Matt Creenan 05-Mar-2010 06:39


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.