无线级分类的一些常用函数

    <?php
/*
* 无限极分类 类
*/
header("Content-Type: text/html; charset=UTF-8");
Class Category {

//组合一维数组
Static Public function unlimitedForLevel ($cate, $html = '--', $pid = 0, $level = 0) {
$arr = array();
foreach ($cate as $k => $v) {
if ($v['pid'] == $pid) {
$v['level'] = $level + 1;
$v['html'] = str_repeat($html, $level);
$arr[] = $v;
$arr = array_merge($arr, self::unlimitedForLevel($cate, $html, $v['id'], $level + 1));
}
}
return $arr;
}

//组合多维数组
Static Public function unlimitedForLayer ($cate, $name = 'child', $pid = 0) {
$arr = array();
foreach ($cate as $v) {
if ($v['pid'] == $pid) {
$v[$name] = self::unlimitedForLayer($cate, $name, $v['id']);
$arr[] = $v;
}
}
return $arr;
}

//传递一个子分类ID返回所有的父级分类
Static Public function getParents ($cate, $id) {
$arr = array();
foreach ($cate as $v) {
if ($v['id'] == $id) {
$arr[] = $v;
$arr = array_merge(self::getParents($cate, $v['pid']), $arr);
}
}
return $arr;
}

//传递一个父级分类ID返回所有子分类ID
Static Public function getChildsId ($cate, $pid) {
$arr = array();
foreach ($cate as $v) {
if ($v['pid'] == $pid) {
$arr[] = $v['id'];
$arr = array_merge($arr, self::getChildsId($cate, $v['id']));
}
}
return $arr;
}

//传递一个父级分类ID返回所有子分类
Static Public function getChilds ($cate, $pid) {
$arr = array();
foreach ($cate as $v) {
if ($v['pid'] == $pid) {
$arr[] = $v;
$arr = array_merge($arr, self::getChilds($cate, $v['id']));
}
}
return $arr;
}


}

$cate = array(
0 => array('id' => 1, 'pid' => 0, 'name' => '江西省'),
1 => array('id' => 2, 'pid' => 0, 'name' => '浙江省'),
2 => array('id' => 3, 'pid' => 1, 'name' => '上饶市'),
3 => array('id' => 4, 'pid' => 3, 'name' => '广丰县'),
4 => array('id' => 5, 'pid' => 2, 'name' => '杭州市'),
5 => array('id' => 6, 'pid' => 5, 'name' => '西湖'),
6 => array('id' => 7, 'pid' => 6, 'name' => '断桥'),
);
print_r(Category::unlimitedForLevel($cate));
print_r(Category::unlimitedForLayer($cate));
print_r(Category::getParents($cate,7));
print_r(Category::getChildsId($cate,2));
print_r(Category::getChilds($cate,2));

来源于：https://www.cnblogs.com/lixihuan/p/7229632.html