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:
$a = array(
"4" => array(
"id" => 4,
"parent" => 0,
array(
"5" => array(
"id" => 5,
"parent" => 4,
array(
"6" => array(
"id" => 6,
"parent" => 5,
array(
"7" => array(
"id" => 7,
"parent" => 6
)
)
)
)
)
)
),
"2" => array(
"id" => 7,
"parent" => 1,
array(
"3" => array(
"id" => 7,
"parent" => 2
)
)
),
"1" => array(
"id" => 7,
"parent" => 0
)
);
我使用的代码是这样的:
foreach($a as $v)
{
if(isset($a[$v['PARENT']]))
{
$a[$v['PARENT']][$v['ID']] = $v;
unset($a[$v['ID']]);
}
}
而我遇到的问题是我得到了这个结果:
$a = array(
"4" => array(
"id" => 4,
"parent" => 0,
array(
"5" => array(
"id" => 5,
"parent" => 4
)
)
),
"2" => array(
"id" => 7,
"parent" => 1,
array(
"3" => array(
"id" => 7,
"parent" => 2
)
)
),
"1" => array(
"id" => 7,
"parent" => 0
)
);
而不是它的结果.
解决方法:
要解决您的问题,您需要正确理解variable referencing/aliasing in PHP的工作原理.
请看下面的示例代码,它与您的代码看起来没什么不同,但是使用引用来访问任何父代,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的所有值 – 但重新排序. Demo.