小编vl4*_*409的帖子

下面的代码说明了PHP引用的奇怪行为:

<?php

function this_works()
{
    $root = array('name'=>'root', 'children'=>array());
    $level_1 = array('name'=>'level_1', 'children'=>array());
    $item1 = array('name'=>'level_2_1', 'children'=>array());
    $item2 = array('name'=>'level_2_2', 'children'=>array());

    $croot = &$root;

    $croot['children'][] = &$level_1;

    $croot = &$level_1;

    $croot['children'][] = &$item1;
    $croot['children'][] = &$item2;

    $croot = &$root;

    print_r($croot);
}    

function this_fails()
{    
    $root = array('name'=>'root', 'children'=>array());
    $level_1 = array('name'=>'level_1', 'children'=>array());
    $item1 = array('name'=>'level_2_1', 'children'=>array());
    $item2 = array('name'=>'level_2_2', 'children'=>array());
    $croot = &$root;

    $stack = array();

    $croot['children'][] = &$level_1;
    $crootref = &$croot;

    array_push($stack, $crootref);

    $croot = &$level_1;

    $croot['children'][] = &$item1; …