代码演示
没什么可说的直接看代码
<?php
namespace app\controller;
class Category
{
private $three; //用户存放没有下级分类的数据
//模拟假数据
protected static function arr()
{
$rows = [
[
‘id‘ => ‘1‘,
‘name‘ => ‘一级菜单‘,
‘pid‘ => ‘0‘,
‘path‘ => ‘0‘,
],
[
‘id‘ => ‘2‘,
‘name‘ => ‘二级菜单‘,
‘pid‘ => ‘0‘,
‘path‘ => ‘0‘,
],
[
‘id‘ => ‘3‘,
‘name‘ => ‘一级菜单-1‘,
‘pid‘ => ‘1‘,
‘path‘ => ‘0-1‘,
],
[
‘id‘ => ‘4‘,
‘name‘ => ‘二级菜单-1‘,
‘pid‘ => ‘2‘,
‘path‘ => ‘0-2‘,
],
[
‘id‘ => ‘5‘,
‘name‘ => ‘一级菜单-1-1‘,
‘pid‘ => ‘3‘,
‘path‘ => ‘0-1-3‘,
],
[
‘id‘ => ‘6‘,
‘name‘ => ‘二级菜单-1-1‘,
‘pid‘ => ‘4‘,
‘path‘ => ‘0-2-4‘,
],
[
‘id‘ => ‘7‘,
‘name‘ => ‘二级菜单-1-2‘,
‘pid‘ => ‘4‘,
‘path‘ => ‘0-2-4‘,
],
[
‘id‘ => ‘8‘,
‘name‘ => ‘三级菜单‘,
‘pid‘ => ‘0‘,
‘path‘ => ‘0‘,
],
[
‘id‘ => ‘9‘,
‘name‘ => ‘二级菜单-1-3‘,
‘pid‘ => ‘4‘,
‘path‘ => ‘0-2-4-6‘,
],
[
‘id‘ => ‘10‘,
‘name‘ => ‘三级菜单-1‘,
‘pid‘ => ‘8‘,
‘path‘ => ‘0-8‘,
],
[
‘id‘ => ‘11‘,
‘name‘ => ‘一级菜单-1-4‘,
‘pid‘ => ‘5‘,
‘path‘ => ‘0-8‘,
],
];
return $rows;
}
public function index()
{
//获取从第0级下的所有分类（pid==0）
$list = $this->build_tree(0);
$data = [
‘list‘ => $list,//无限级分类数据
‘three‘ => $this->three,//最小等级，没有下级分类非数据
];
return json($data);
}
/**
* 递归子级
* @param $list
* @param $id
* @return array
*/
public function findChild($list, $id)
{
$child = [];
foreach ($list as $key => $item) {
//如果pid等于传进来的if
if ($item[‘pid‘] == $id) {
$child[] = $item;
}
}
return $child;
}
/**
* 获取当前级别的子级
* @param $root_id /第几层
* @return null
*/
public function build_tree($root_id)
{
//获取假数据
$list = $this->arr();
//查找指定级数
$tree = $this->findChild($list, $root_id);
if (empty($tree)) {
return null;
}
//遍历获取到的层级得到下级分类
foreach ($tree as $key => $item) {
//递归调用自己 查找每个元素下的分类
$child = $this->build_tree($item[‘id‘]);
//如果有子类就放入数组中
if ($child != null){
$tree[$key][‘child‘] = $child;
}else{ //获取没有下级分类的数据 也就是最底级
$this->three[] = $item;
}
}
return $tree;
}
}