tp5.1 无限极分类前台展示

 $DB = new Db;
        // if(!$data){

          $data = $DB::table("wuxian")->where(‘pid‘,0)->select();//获取一级分类数组
          
          foreach($data as $k=>$v){//k=0
            $id = $data[$k][‘id‘];
            $data2 = $DB::table("wuxian")->where(‘pid‘,$id)->select();//获取二级分类数组
            
            // 
            $data[$k][‘child‘] = $data2;//组装二级到一级数组data
             
            
              foreach($data2 as $k2 => $v2){//k2=

                $id2 = $data2[$k2][‘id‘];
                
                $data3 = $DB::table("wuxian")->where(‘pid‘,$id2)->select();//获取三级分类数组
                
                $data[$k][‘child‘][$k2][‘child‘] = $data3;//先找到二级数组，然后组装三级到二级数组data2 
              }
                 
            }