PHP递归实现无限极分类

准备测试数组：

$cates = array(
array(
'id' => 1,
'pid'   =>  0,
'title' =>  'php'
),
array(
'id' => 2,
'pid'   =>  0,
'title' =>  'linux'
),
array(
'id' => 3,
'pid'   =>  0,
'title' =>  'mysql'
),
array(
'id' => 4,
'pid'   =>  1,
'title' =>  'array'
),
array(
'id' => 5,
'pid'   =>  1,
'title' =>  'string'
),
array(
'id' => 6,
'pid'   =>  2,
'title' =>  'nginx'
),
array(
'id' => 7,
'pid'   =>  4,
'title' =>  'array_rand'
),
);

组合：一维数组

function get_cate_list($cates, $pid = 0, $level = 0, $html = '|--'){
$temp = array();
foreach ($cates as $v) {
if ($v['pid'] == $pid) {
$v['level'] = $level + 1;
$v['html'] = str_repeat($html, $level + 1);
$temp[] = $v;
$temp = array_merge($temp, get_cate_list($cates, $v['id'], $level + 1, $html));
}
}
return $temp;
}

组合：多维数组

function get_cate_list_multi($cates, $pid = 0){
$temp = array();
foreach ($cates as $v) {
if ($v['pid'] == $pid) {
$v['child'] = get_cate_list_multi($cates, $v['id']);
$temp[] = $v;
}
}
return $temp;
}

给定父id获取所有子分类

function get_cate_son($cates, $pid = 0){
$temp = array();
foreach ($cates as $v) {
if ($v['pid'] == $pid) {
$temp[] = $v;
$temp = array_merge($temp, get_cate_son($cates, $v['id']));
}
}
return $temp;
}

给定子分类的id获取所有父分类：适用于面包屑导航

function get_cate_parent($cates, $id){
$temp = array();
foreach ($cates as $v) {
if ($v['id'] == $id) {
$temp[] = $v;
$temp = array_merge(get_cate_parent($cates, $v['pid']), $temp);
}
}
return $temp;
}

/* 打印结果 */
$all = get_cate_list($cates);
// $all = get_cate_list_multi($cates);
// $son = get_cate_son($cates, 1);
// $parent = get_cate_parent($cates, 7);

print_r($all);
// print_r($son);
// print_r($parent);