Question

我维护了一些遗留代码，并且我一直在删除对新对象的引用，如：

$object = & new SomeObject();

到此：

$object = new SomeObject();

而且，尽管事实上它不应该有任何区别，因为PHP5确实搞砸了一些非常糟糕的东西，而对象根本不再是一个参考。如果&被替换，则问题就会消失。

以下是一个示例代码：

<?php

class TreeNode
{
    public $subtree;
    public $name;
    public $layer;
    public $children;

    function &addNode(&$node)
    {
        $this->children[] = &$node;
    }

}

$subtree = array(array('bla','blubb'), 'foo');

$tree = new TreeNode();
$tree->subtree = $subtree;
$tree->layer = 0;
$tree->name = 'root';

$b = buildTree($tree);

print_r($b);

function &buildTree(&$tree) {
    if(is_array($tree->subtree))
    {
        foreach($tree->subtree as $key => $subtree)
        {
            $node = new TreeNode(); ///#### This line is a toggle and it's unknown why
            $node->layer = $tree->layer + 1;
            $node->subtree = $subtree;
            $tree->addNode( buildTree($node) );
            unset($tree->subtree[$key]);
        }
    }
    else
    {
        $tree->name = $tree->subtree;
    }

    return $tree;
}

?>

如果该行为$node = new TreeNode();，则输出为： TreeNode对象（ [subtree] =＆gt;排列（）

    [name] => root
    [layer] => 0
    [children] => Array
        (
            [0] => TreeNode Object
                (
                    [subtree] => foo
                    [name] => foo
                    [layer] => 1
                    [children] => 
                )

            [1] => TreeNode Object
                (
                    [subtree] => foo
                    [name] => foo
                    [layer] => 1
                    [children] => 
                )

        )

)

如果该行为$node = & new TreeNode();，则输出为： TreeNode对象（ [subtree] =＆gt;排列（）

    [name] => root
    [layer] => 0
    [children] => Array
        (
            [0] => TreeNode Object
                (
                    [subtree] => Array
                        (
                        )

                    [name] => 
                    [layer] => 1
                    [children] => Array
                        (
                            [0] => TreeNode Object
                                (
                                    [subtree] => bla
                                    [name] => bla
                                    [layer] => 2
                                    [children] => 
                                )

                            [1] => TreeNode Object
                                (
                                    [subtree] => blubb
                                    [name] => blubb
                                    [layer] => 2
                                    [children] => 
                                )

                        )

                )

            [1] => TreeNode Object
                (
                    [subtree] => foo
                    [name] => foo
                    [layer] => 1
                    [children] => 
                )

        )

)

Answer 1

实际上，事实证明这是一个由更多参考文献引起的问题。有问题的代码看起来像这样：

function &recursiveFunction(&$someobject) {
  $object = & new SomeObject();
  $someobject->recursiveFunction($object);
  return $someobject;
}

从函数中删除引用以及使用对象的任何地方最终解决了问题，而无需对创建进行引用。因此，这只是参考本身的一部分问题，也是其他参考文献。

function recursiveFunction($someobject) {
  $object = new SomeObject();
  $someobject->recursiveFunction($object);
  return $someobject;
}

我仍然不确定究竟为什么会发生这种情况，但即使在较新的版本中，处理&$object的PHP内部问题仍可能与$object有所不同对象应该始终是对象本身的引用。

删除参考“＆amp;”来自new Object会导致PHP出现意外问题

1 个答案: