php下拉框树形菜单

http://www.treejs.cn/v3/main.php#_zTreeInfo

来自网上:

  1 <?php
  2 header("content-type:text/html;charset=utf-8");
  3 $menu.= "<select id='sel'>";
  4 function tree_set($index)
  5 {
  6         global $menu,$str;
  7         static $j;
  8         $cn=mysql_connect("127.0.0.1","root","root");
  9         $db=mysql_select_db("test");
 10         $sql = "SELECT * FROM category WHERE parent={$index} AND class_id=1";
 11         mysql_query("set names utf8");
 12         $q = mysql_query($sql);
 13         if(!mysql_num_rows($q)){
 14                 return;
 15         }
 16         $j=$j+1;
 17         while($arr=mysql_fetch_assoc($q))
 18         {
 19                 //echo $j;
 20                 for ($i = 0 ; $i < $j; $i++){
 21                         $str .= '|';//几级菜单几条竖线
 22                 }
 23                 $str.= '---';
 24                 $menu.= "<option value=".$arr['cat_id'].">";
 25                 $menu.= $str.$arr['cat_name'];
 26                 $menu.= '</option>';
 27                 $str = '';
 28                 tree_set($arr['cat_id']);
 29         }
 30         $str = '';
 31 }
 32 function write_html()
 33 {
 34         global $menu;
 35         tree_set(0);
 36         $menu.= '</select>';
 37         echo $menu;
 38
 39 }
 40 write_html();