嵌套数组第三层正在消失

如何解决嵌套数组第三层正在消失

要解决您的问题，您需要正确地理解PHP中变量引用/别名的工作方式。

看下面的示例代码，它看起来与您的代码没有太大不同，但是利用引用来访问任何父对象，即使它已经“移动”了：

# transform $flat into a tree:
foreach($flat as $id => &$value)
{
    # check if there is a parent
    if ($parentId = $value['parent'])
    {
        $flat[$parentId][0][$id] =& $value; # add child to parent
        unset($flat[$id]); # remove reference from topmost level
    }
}
unset($value); # remove iterator reference
print_r($flat); # your tree

$flat现在包含$flat- 中的所有值，但已重新排序。

解决方法

我有那个数组：

$a = array(
    "7" => array(
        "id" => 7,"parent" => 6
    ),"6" => array(
        "id" => 6,"parent" => 5
    ),"5" => array(
        "id" => 5,"parent" => 4
    ),"4" => array(
        "id" => 4,"parent" => 0
    ),"3" => array(
        "id" => 7,"parent" => 2
    ),"2" => array(
        "id" => 7,"parent" => 1
    ),"1" => array(
        "id" => 7,"parent" => 0
    )
);

我想要的结果是：

$a = array(
    "4" => array(
        "id" => 4,"parent" => 0,array(
            "5" => array(
                "id" => 5,"parent" => 4,array(
                    "6" => array(
                        "id" => 6,"parent" => 5,array(
                            "7" => array(
                                "id" => 7,"parent" => 6
                            )
                        )
                    )
                )
            )
        )
    ),"parent" => 1,array(
            "3" => array(
                "id" => 7,"parent" => 2
            )
        )
    ),"parent" => 0
    )
);

我使用的代码是这样的：

foreach($a as $v)
{
    if(isset($a[$v['PARENT']]))
    {
        $a[$v['PARENT']][$v['ID']] = $v;
        unset($a[$v['ID']]);
    }
}

我的问题是我得到了那个结果：

$a = array(
    "4" => array(
        "id" => 4,"parent" => 4
            )
        )
    ),"parent" => 0
    )
);

而不是需要它的结果。