PHP 无限级缩进分类
PHP 无限极分类经常被使用应用，如菜单无限极分类，国家省市级分类，商城等等
核心类
比如在TP6中使用 代码路径
项目文件夹/extend 新建 holyrisk文件夹 Tree.php
<?php
namespace holyrisk;
class Tree
{
/**
* @description 无限极分类实现 - 嵌套形式
* @author Holyrisk
* @date 2021/4/22 22:41
* @param $list 需要被处理的数组
* @param string $pk id
* @param string $pid 父级id
* @param string $child 子级名称
* @param int $root 顶级分类的值
* @return array
*/
public function buildTree($list, $pk='id', $pid='pid', $child='children', $root=0){
if (empty($list)){
return [];
}
$tree = array();
$packData = array();
foreach ($list as $data) {
$packData[$data[$pk]] = $data;
}
foreach ($packData as $key=>$val){
if($val[$pid] == $root){
$tree[] = &$packData[$key];
}else{
$packData[$val[$pid]][$child][] = &$packData[$key];
}
}
return $tree;
}
/**
* 无限极分类实现 - 列表形式 取得等级 级别
* @param $array 分类数据
* @param $pid 父ID
* @param $level 分类级别
* @return array 分好类的数组 直接遍历即可 $level可以用来遍历缩进
*/
public function getTreeLevel($array, $pid =0, $level = 0){
//声明静态数组,避免递归调用时,多次声明导致数组覆盖
static $list = [];
foreach ($array as $key => $value){
//第一次遍历,找到父节点为根节点的节点 也就是pid=0的节点
if ($value['pid'] == $pid){
//父节点为根节点的节点,级别为0，也就是第一级
$value['level'] = $level;
//把数组放到list中
$list[] = $value;
//把这个节点从数组中移除,减少后续递归消耗
unset($array[$key]);
//开始递归,查找父ID为该节点ID的节点,级别则为原级别+1
$this->getTreeLevel($array, $value['id'], $level+1);
}
}
return $list;
}
/**
* 缩进形式 无限级 分类
* 参考 https://www.cnblogs.com/phpk/p/10929918.html
* @param $array
* @param int $pid
* @param int $level
* @return array
*/
public function getTreeHtmlSelect($array, $pid =0, $level = 0)
{
$list = $this->getTreeLevel($array,$pid,$level);
foreach ($list as $key => $value){
$list[$key]['name'] = str_repeat('>>', $value['level']). $value['name'];
}
return $list;
}
}代码调用演示
use holyrisk\Tree;
$array = array(
array('id' => 1, 'pid' => 0, 'name' => '河北省'),
array('id' => 2, 'pid' => 0, 'name' => '北京市'),
array('id' => 3, 'pid' => 1, 'name' => '邯郸市'),
array('id' => 4, 'pid' => 2, 'name' => '朝阳区'),
array('id' => 5, 'pid' => 2, 'name' => '通州区'),
array('id' => 6, 'pid' => 4, 'name' => '望京'),
array('id' => 7, 'pid' => 4, 'name' => '酒仙桥'),
array('id' => 8, 'pid' => 3, 'name' => '永年区'),
array('id' => 9, 'pid' => 1, 'name' => '武安市'),
);
$son = (new Tree())->buildTree($array);
$list = (new Tree())->getTreeLevel($array);
$arr = (new Tree())->getTreeHtmlSelect($array);
echo "<pre>";
echo "原始数据"."<br />";
echo print_r($array);
echo "嵌套形式"."<br />";
echo print_r($son);
echo "列表级别形式"."<br />";
echo print_r($list);
echo "列表缩进 - 给HTML下拉框使用形式"."<br />";
echo print_r($arr);
echo "</pre>";输出打印
原始数据 Array ( [0] => Array ( [id] => 1 [pid] => 0 [name] => 河北省 ) [1] => Array ( [id] => 2 [pid] => 0 [name] => 北京市 ) [2] => Array ( [id] => 3 [pid] => 1 [name] => 邯郸市 ) [3] => Array ( [id] => 4 [pid] => 2 [name] => 朝阳区 ) [4] => Array ( [id] => 5 [pid] => 2 [name] => 通州区 ) [5] => Array ( [id] => 6 [pid] => 4 [name] => 望京 ) [6] => Array ( [id] => 7 [pid] => 4 [name] => 酒仙桥 ) [7] => Array ( [id] => 8 [pid] => 3 [name] => 永年区 ) [8] => Array ( [id] => 9 [pid] => 1 [name] => 武安市 ) ) 1嵌套形式 Array ( [0] => Array ( [id] => 1 [pid] => 0 [name] => 河北省 [children] => Array ( [0] => Array ( [id] => 3 [pid] => 1 [name] => 邯郸市 [children] => Array ( [0] => Array ( [id] => 8 [pid] => 3 [name] => 永年区 ) ) ) [1] => Array ( [id] => 9 [pid] => 1 [name] => 武安市 ) ) ) [1] => Array ( [id] => 2 [pid] => 0 [name] => 北京市 [children] => Array ( [0] => Array ( [id] => 4 [pid] => 2 [name] => 朝阳区 [children] => Array ( [0] => Array ( [id] => 6 [pid] => 4 [name] => 望京 ) [1] => Array ( [id] => 7 [pid] => 4 [name] => 酒仙桥 ) ) ) [1] => Array ( [id] => 5 [pid] => 2 [name] => 通州区 ) ) ) ) 1列表级别形式 Array ( [0] => Array ( [id] => 1 [pid] => 0 [name] => 河北省 [level] => 0 ) [1] => Array ( [id] => 3 [pid] => 1 [name] => 邯郸市 [level] => 1 ) [2] => Array ( [id] => 8 [pid] => 3 [name] => 永年区 [level] => 2 ) [3] => Array ( [id] => 9 [pid] => 1 [name] => 武安市 [level] => 1 ) [4] => Array ( [id] => 2 [pid] => 0 [name] => 北京市 [level] => 0 ) [5] => Array ( [id] => 4 [pid] => 2 [name] => 朝阳区 [level] => 1 ) [6] => Array ( [id] => 6 [pid] => 4 [name] => 望京 [level] => 2 ) [7] => Array ( [id] => 7 [pid] => 4 [name] => 酒仙桥 [level] => 2 ) [8] => Array ( [id] => 5 [pid] => 2 [name] => 通州区 [level] => 1 ) ) 1列表缩进 - 给HTML下拉框使用形式 Array ( [0] => Array ( [id] => 1 [pid] => 0 [name] => 河北省 [level] => 0 ) [1] => Array ( [id] => 3 [pid] => 1 [name] => >>邯郸市 [level] => 1 ) [2] => Array ( [id] => 8 [pid] => 3 [name] => >>>>永年区 [level] => 2 ) [3] => Array ( [id] => 9 [pid] => 1 [name] => >>武安市 [level] => 1 ) [4] => Array ( [id] => 2 [pid] => 0 [name] => 北京市 [level] => 0 ) [5] => Array ( [id] => 4 [pid] => 2 [name] => >>朝阳区 [level] => 1 ) [6] => Array ( [id] => 6 [pid] => 4 [name] => >>>>望京 [level] => 2 ) [7] => Array ( [id] => 7 [pid] => 4 [name] => >>>>酒仙桥 [level] => 2 ) [8] => Array ( [id] => 5 [pid] => 2 [name] => >>通州区 [level] => 1 ) [9] => Array ( [id] => 1 [pid] => 0 [name] => 河北省 [level] => 0 ) [10] => Array ( [id] => 3 [pid] => 1 [name] => >>邯郸市 [level] => 1 ) [11] => Array ( [id] => 8 [pid] => 3 [name] => >>>>永年区 [level] => 2 ) [12] => Array ( [id] => 9 [pid] => 1 [name] => >>武安市 [level] => 1 ) [13] => Array ( [id] => 2 [pid] => 0 [name] => 北京市 [level] => 0 ) [14] => Array ( [id] => 4 [pid] => 2 [name] => >>朝阳区 [level] => 1 ) [15] => Array ( [id] => 6 [pid] => 4 [name] => >>>>望京 [level] => 2 ) [16] => Array ( [id] => 7 [pid] => 4 [name] => >>>>酒仙桥 [level] => 2 ) [17] => Array ( [id] => 5 [pid] => 2 [name] => >>通州区 [level] => 1 ) )