递归无限极分类

header("Content-Type:text/html;charset=UTF-8");
echo "
";
$area = array(
    array('id'=>1,'area'=>'北京','pid'=>0),
    array('id'=>2,'area'=>'广西','pid'=>0),
    array('id'=>3,'area'=>'广东','pid'=>0),
    array('id'=>4,'area'=>'福建','pid'=>0),
    array('id'=>11,'area'=>'朝阳区','pid'=>1),
    array('id'=>12,'area'=>'海淀区','pid'=>1),
    array('id'=>21,'area'=>'南宁市','pid'=>2),
    array('id'=>45,'area'=>'福州市','pid'=>4),
    array('id'=>113,'area'=>'亚运村','pid'=>11),
    array('id'=>115,'area'=>'奥运村','pid'=>11),
    array('id'=>234,'area'=>'武鸣县','pid'=>21)
);

function digui($arr,$pid=0,$lev=0){
       $list = array();
    foreach($arr as $v){
        if($v['pid']==$pid){
            echo $v['html'] = str_repeat("----",$lev).$v['area']."
";
            $list[]= $v;
            digui($arr,$v['id'],$lev+1);
        }
    }
    return $list;
}

$list =digui($area);
echo "
";
print_r($list);