删除引用“&&引用；来自新对象会导致PHP中出现意外问题
我正在维护一些遗留代码，并一直在删除对新对象的引用，如：删除引用“&&引用；来自新对象会导致PHP中出现意外问题,php,Php,我正在维护一些遗留代码，并一直在删除对新对象的引用，如： $object = & new SomeObject(); [name] => root [layer] => 0 [children] => Array ( [0] => TreeNode Object ( [subtree] => foo
$object = & new SomeObject();
[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] =>
)
)
)
[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] =>
)
)
)
$object = new SomeObject();
[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] =>
)
)
)
[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] =>
)
)
)
& [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] =>
)
)
)
[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] =>
)
)
)
<?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;
}
?>
[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] =>
)
)
)
[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] =>
)
)
)
$node=&new TreeNode（）输出为：
树状物
(
[子树]=>数组
(
)
[name] => root
[layer] => 0
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
[1] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
)
)
[name] => root
[layer] => 0
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => Array
(
)
[name] =>
[layer] => 1
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => bla
[name] => bla
[layer] => 2
[children] =>
)
[1] => TreeNode Object
(
[subtree] => blubb
[name] => blubb
[layer] => 2
[children] =>
)
)
)
[1] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
)
)
事实上，这是一个由更多引用引起的问题。相关代码如下所示：
[name] => root
[layer] => 0
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
[1] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
)
)
[name] => root
[layer] => 0
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => Array
(
)
[name] =>
[layer] => 1
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => bla
[name] => bla
[layer] => 2
[children] =>
)
[1] => TreeNode Object
(
[subtree] => blubb
[name] => blubb
[layer] => 2
[children] =>
)
)
)
[1] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
)
)
function &recursiveFunction(&$someobject) {
$object = & new SomeObject();
$someobject->recursiveFunction($object);
return $someobject;
}
从函数和对象使用的任何地方删除引用，最终解决了问题，而不必在创建时也有引用。因此，这只是引用本身的一部分问题，但周围也有其他引用
[name] => root
[layer] => 0
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
[1] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
)
)
[name] => root
[layer] => 0
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => Array
(
)
[name] =>
[layer] => 1
[children] => Array
(
[0] => TreeNode Object
(
[subtree] => bla
[name] => bla
[layer] => 2
[children] =>
)
[1] => TreeNode Object
(
[subtree] => blubb
[name] => blubb
[layer] => 2
[children] =>
)
)
)
[1] => TreeNode Object
(
[subtree] => foo
[name] => foo
[layer] => 1
[children] =>
)
)
)
function recursiveFunction($someobject) {
$object = new SomeObject();
$someobject->recursiveFunction($object);
return $someobject;
}
我仍然有点不确定为什么会发生这种情况，但这可能是PHP内部处理&$object
的一些问题，仍然与$object
不同，即使在较新版本中，对象应该始终是对象本身的引用。内部处理没有任何问题，并且发布了错误(s)下次提问时，您可能会得到一些信息，这些信息可能会帮助其他人告诉您出了什么问题、为什么出了问题以及如何避免。问题是函数似乎会为所有对象返回对同一对象的引用。因此，返回的所有对象最终都是同一对象。我们使用此信息来呈现导航树，并在&在新节点被删除时，它在所有节点上显示相同的文本和链接，因为所有节点都获得了该函数创建的最后一个节点的内容。如果所有的和都已就位，或者没有一个正确工作。我添加了一些示例代码，展示了相同的问题，以便您可以对其进行实验。这让我感到非常困惑对于使用引用或不使用引用传递的对象，应该不再有任何区别。
[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] =>
)
)
)
[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] =>
)
)
)