省市县三级联动

mysql 数据库里规定 city 表 省 市 县，如何使用php 循环三级数组

     
  /* $prvicelist =  Db::name("system_city")->field("city_id,parent_id,name as text")->where("parent_id",0)->select()->toArray();
    
    foreach ( $prvicelist as $k=>$v){
        
         $citylist =  Db::name("system_city")->field("city_id,parent_id,name as text")->where("parent_id",$v["city_id"])->select()->toArray();
         
         $prvicelist[$k]=$v;
           foreach ( $citylist as $kk=>$vv){
         
             $prvicelist[$k]["children"][$kk]=$vv;
             
             
           $cityxian =  Db::name("system_city")->field("city_id,parent_id,name as text")->where("parent_id",$vv["city_id"])->select()->toArray();
       
                 foreach ( $cityxian as $kkk=>$vvv){
                     
                        $prvicelist[$k]["children"][$kk]["children"][$kkk]=$vvv;
                     
                     
                 }
         
           }
    
    }
     

循环出的格式[ { text: '浙江', children: [ { text: '杭州', children: [{ text: '西湖区' }, { text: '余杭区' }], }, { text: '温州', children: [{ text: '鹿城区' }, { text: '瓯海区' }], }, ], }, { text: '福建', children: [ { text: '福州', children: [{ text: '鼓楼区' }, { text: '台江区' }], }, { text: '厦门', children: [{ text: '思明区' }, { text: '海沧区' }], }, ], }, ];

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