//无限分类$list=array(array('id'=>1,'pid'=>0,'name'=>'河北省'),array('id'=>2,'pid'=>0,'name'=>'北京'),array('id'=>3,'pid'=>1,'name'=>'邯郸'),array('id'=>4,'pid'=>2,'name'=>'朝阳区'),array('id'=>5,'pid'=>2,'name'=>'通州区'),array('id'=>6,'pid'=>4,'name'=>'望京'),array('id'=>7,'pid'=>4,'name'=>'酒仙桥'),array('id'=>8,'pid'=>3,'name'=>'永年区'),array('id'=>9,'pid'=>1,'name'=>'武安市'),array('id'=>10,'pid'=>7,'name'=>'三邻'),);//传值引用函数list_to_tree($list,$id='id',$pid='pid',$child='_child',$root=0){$tree=[];if(is_array($list)){//根据主键创建数组引用$refer=[];foreach($listas$k=>$v){$refer[$v[$id]]=&$list[$k];}foreach($listas$k=>$v){$parent_id=$v[$pid];如果（$root==$parent_id）{$tree[]=&$list[$k];}else{if(isset($refer[$parent_id])){$parent=&$refer[$parent_id];$parent[$child][]=&$list[$k];}}}}return$tree;}//递归functiongetTree($data,$pId){$tree=array();foreach($dataas$k=>$v){if($v['pid']==$pId){//父亲找到儿子$v['_child']=getTree($data,$v['ID']）;$树[]=$v;取消设置（$数据[$k]）；}}返回$tree;}
