PHP+Mysql实现无限菜单分类

<?php//数据库链接$link = mysqli_connect('主机','用户名','密码','数据库'); // 检查连接 if (!$link) {     die("连接错误: " . mysqli_connect_error()); }$sql = "select id,pid from abc";$rel = mysqli_query($link,$sql);$data = mysqli_fetch_all($rel,MYSQL_ASSOC);/** * 无限极 * @param      $data   待分类的数据 * @param      $id     父级id * @param      $lev    节点等级 */ function treeMenu($data , $id = 0 , $lev = 0) {     static $son = array();     foreach($data as $key => $value) {         if($value['pid'] == $id) {             $value['lev'] = $lev;             $son[] = $value;             treeMenu($data , $value['id'] , $lev+1);         }     }     return $son; }$tree = treeMenu($data , 0 , 0); foreach($tree as $k => $v) {    echo str_repeat('--' , $v['lev']) . $v['id'] . '<br/>';}