<?php
namespace app\common\utils;
//一个生成树的类库
class TreeUtils
{

    public static function sort($dataArr, $rootId = 0, $pkName = 'id', $pIdName = 'pid', $childName = 'children')
    {
        $arr = [];
        foreach ($dataArr as $sorData) {
            if ($sorData[$pIdName] == $rootId) {
                $children = TreeUtils::sort($dataArr, $sorData[$pkName]);
                if($children){
                    $sorData[$childName] = $children;
                }
                $arr[] = $sorData;
            }
        }
        return $arr;
    }
}

$dataArr：数据列表 $rootId：顶级ID值 $pkName：主键ID $pIdName：PID对应字段 $childName：生成树形后的对应子项字段名