我有这个扁平数组，我试图变成一个父子数组：
Array
(
[0] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze7b2e
)
[1] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_czeg8ay
)
[2] => Array
(
[parent_id] => t1_czeg8ay
[id] => t1_czet481
)
[3] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze4whs
)
[4] => Array
(
[parent_id] => t1_cze4whs
[id] => t1_cze9v0o
)
[5] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czec4vd
)
[6] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czep9e2
)
[7] => Array
(
[parent_id] => t1_czep9e2
[id] => t1_czf2k8e
)
[8] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czeixa7
)
[9] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czecx26
)
[10] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeenuz
)
[11] => Array
(
[parent_id] => t1_czeenuz
[id] => t1_czeftkf
)
[12] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czehjrz
)
[13] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeien4
)
[14] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czebugl
)
[15] => Array
(
[parent_id] => t1_cze4whs
[id] => t1_cze9hvb
)
[16] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze3vku
)
[17] => Array
(
[parent_id] => t1_cze3vku
[id] => t1_czemk0g
)
[18] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_czeedh9
)
[19] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_czeenjx
)
[20] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze5r5u
)
[21] => Array
(
[parent_id] => t1_cze5r5u
[id] => t1_czefle4
)
[22] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze8oht
)
[23] => Array
(
[parent_id] => t1_cze8oht
[id] => t1_czelwvs
)
[24] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze5cs6
)
[25] => Array
(
[parent_id] => t1_cze5cs6
[id] => t1_czefydi
)
[26] => Array
(
[parent_id] => t1_cze5cs6
[id] => t1_czedpml
)
[27] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze42aq
)
[28] => Array
(
[parent_id] => t1_cze42aq
[id] => t1_cze8iei
)
[29] => Array
(
[parent_id] => t1_cze8iei
[id] => t1_czebkgk
)
[30] => Array
(
[parent_id] => t1_czebkgk
[id] => t1_czedid2
)
[31] => Array
(
[parent_id] => t1_cze8iei
[id] => t1_czebqgn
)
[32] => Array
(
[parent_id] => t1_cze42aq
[id] => t1_cze77xr
)
[33] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_czen20j
)
)
这是我的递归函数，它映射id并使其成为父子数组：
function buildTree(array $elements, $parentId = 0) {
$branch = array();
foreach ($elements as $element) {
if ($element['parent_id'] == $parentId) {
$children = buildTree($elements, $element['id']);
if ($children) {
$element['children'] = $children;
}
$branch[] = $element;
}
}
return $branch;
}
以下是我从上述函数获得的输出：
Array
(
[0] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze7b2e
)
[1] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_czeg8ay
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czeg8ay
[id] => t1_czet481
)
)
)
[2] => Array
(
[parent_id] => t1_czeg8ay
[id] => t1_czet481
)
[3] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze4whs
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze4whs
[id] => t1_cze9v0o
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czec4vd
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czep9e2
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czep9e2
[id] => t1_czf2k8e
)
)
)
[1] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czeixa7
)
)
)
[1] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czecx26
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeenuz
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czeenuz
[id] => t1_czeftkf
)
)
)
[1] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czehjrz
)
[2] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeien4
)
)
)
[2] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czebugl
)
)
)
[1] => Array
(
[parent_id] => t1_cze4whs
[id] => t1_cze9hvb
)
)
)
[4] => Array
(
[parent_id] => t1_cze4whs
[id] => t1_cze9v0o
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czec4vd
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czep9e2
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czep9e2
[id] => t1_czf2k8e
)
)
)
[1] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czeixa7
)
)
)
[1] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czecx26
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeenuz
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czeenuz
[id] => t1_czeftkf
)
)
)
[1] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czehjrz
)
[2] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeien4
)
)
)
[2] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czebugl
)
)
)
[5] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czec4vd
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czep9e2
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czep9e2
[id] => t1_czf2k8e
)
)
)
[1] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czeixa7
)
)
)
[6] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czep9e2
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czep9e2
[id] => t1_czf2k8e
)
)
)
[7] => Array
(
[parent_id] => t1_czep9e2
[id] => t1_czf2k8e
)
[8] => Array
(
[parent_id] => t1_czec4vd
[id] => t1_czeixa7
)
[9] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czecx26
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeenuz
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czeenuz
[id] => t1_czeftkf
)
)
)
[1] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czehjrz
)
[2] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeien4
)
)
)
[10] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeenuz
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czeenuz
[id] => t1_czeftkf
)
)
)
[11] => Array
(
[parent_id] => t1_czeenuz
[id] => t1_czeftkf
)
[12] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czehjrz
)
[13] => Array
(
[parent_id] => t1_czecx26
[id] => t1_czeien4
)
[14] => Array
(
[parent_id] => t1_cze9v0o
[id] => t1_czebugl
)
[15] => Array
(
[parent_id] => t1_cze4whs
[id] => t1_cze9hvb
)
[16] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze3vku
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze3vku
[id] => t1_czemk0g
)
)
)
[17] => Array
(
[parent_id] => t1_cze3vku
[id] => t1_czemk0g
)
[18] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_czeedh9
)
[19] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_czeenjx
)
[20] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze5r5u
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze5r5u
[id] => t1_czefle4
)
)
)
[21] => Array
(
[parent_id] => t1_cze5r5u
[id] => t1_czefle4
)
[22] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze8oht
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze8oht
[id] => t1_czelwvs
)
)
)
[23] => Array
(
[parent_id] => t1_cze8oht
[id] => t1_czelwvs
)
[24] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze5cs6
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze5cs6
[id] => t1_czefydi
)
[1] => Array
(
[parent_id] => t1_cze5cs6
[id] => t1_czedpml
)
)
)
[25] => Array
(
[parent_id] => t1_cze5cs6
[id] => t1_czefydi
)
[26] => Array
(
[parent_id] => t1_cze5cs6
[id] => t1_czedpml
)
[27] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_cze42aq
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze42aq
[id] => t1_cze8iei
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze8iei
[id] => t1_czebkgk
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czebkgk
[id] => t1_czedid2
)
)
)
[1] => Array
(
[parent_id] => t1_cze8iei
[id] => t1_czebqgn
)
)
)
[1] => Array
(
[parent_id] => t1_cze42aq
[id] => t1_cze77xr
)
)
)
[28] => Array
(
[parent_id] => t1_cze42aq
[id] => t1_cze8iei
[children] => Array
(
[0] => Array
(
[parent_id] => t1_cze8iei
[id] => t1_czebkgk
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czebkgk
[id] => t1_czedid2
)
)
)
[1] => Array
(
[parent_id] => t1_cze8iei
[id] => t1_czebqgn
)
)
)
[29] => Array
(
[parent_id] => t1_cze8iei
[id] => t1_czebkgk
[children] => Array
(
[0] => Array
(
[parent_id] => t1_czebkgk
[id] => t1_czedid2
)
)
)
[30] => Array
(
[parent_id] => t1_czebkgk
[id] => t1_czedid2
)
[31] => Array
(
[parent_id] => t1_cze8iei
[id] => t1_czebqgn
)
[32] => Array
(
[parent_id] => t1_cze42aq
[id] => t1_cze77xr
)
[33] => Array
(
[parent_id] => t3_42yrg7
[id] => t1_czen20j
)
)
虽然它的第一部分是正确的，但它有时会在第一次正确映射后将子数组标记为父类。为什么有些子数组被映射为父数组？</ p>
编辑：我是个白痴，当我打电话给buildTree()时，我没有传入一个parentId，只是将该值保留为零。
答案 0 :(得分：1)
我不知道你想要什么，但我已将我的代码添加到数组中的父和子分开。请查看以下代码：
function buildTree($elements = array()) {
$branch = array();
if(!empty($elements))
{
foreach ($elements as $element) {
if(!isset($branch[$element['parent_id']]))
{
$branch['parent_id'][]=$element['parent_id'];
$branch[$element['parent_id']]=array();
$branch[$element['parent_id']]['children'][]=$element['id'];
}
else
{
$branch[$element['parent_id']]['children'][]=$element['id'];
}
}
}
return $branch;
}
$arr_rtn = buildTree($arr);