<?     //树型目录结构模板程序     //菜单目录库字段说明:     //menu_id 菜单项目 id     //menu 菜单名称     //menu_grade 菜单等级 1 为主菜单 2 为二级菜单 ........     //menu_superior 上一级菜单 id 号     function my_menu($menu_content,$i,$menu_grade_temp,$menu_superior_temp)     {       global $PHP_SELF;       $temp1=$menu_grade_temp+1;       $menu_superior_temp_array=split("/",$menu_superior_temp);       for ($t=0;$t<$i;$t++)       {         $menu_array=split("/",$menu_content[$t]);         If(($menu_array[2]==$menu_grade_temp)&&($menu_array[3]==$menu_superior_temp_array[$menu_grade_temp-1]))         {           for($p=1;$p<=$menu_grade_temp;$p++){echo "  ";}           $temp3=$menu_superior_temp_array;           $temp3[$menu_grade_temp]=$menu_array[0];           $temp2=implode("/",$temp3);           if ($menu_array[0]==$menu_superior_temp_array[$temp1-1])           {             $temp5=$temp1-1;             $temp3[$menu_grade_temp]="";             $temp6=implode("/",$temp3);             echo "<a href="$PHP_SELF?menu_grade_temp=".$temp5."&menu_superior_temp=$temp6">$menu_array[1]</a><br>";             my_menu($menu_content,$i,$temp1,$temp2);           }           else           {             $temp3[$menu_grade_temp+1]="";             $temp6=implode("/",$temp3);             echo "<a href="$PHP_SELF?menu_grade_temp=".$temp1."&menu_superior_temp=$temp6">$menu_array[1]</a><br>";           }         }       }     }     // 连接 MySql 数据库     $db_host="localhost";     $db_user="dkj";     $db_password="123";     $db_name="test";     mysql_connect($db_host,$db_user,$db_password);     mysql_select_db($db_name);     //从数据库中取得数据     $query_string="select * from menu order by menu_grade";     $db_data=mysql_query($query_string);     //第一次执行初始化     if ($menu_grade_temp=="")     {       $menu_superior_temp=0;     }     //将所有的信息读入数组,并统计数组个数     $i=0;     while (list($menu_id,$menu,$menu_grade,$menu_superior)=mysql_fetch_row($db_data))     {       $menu_content[$i]=$menu_id."/".$menu."/".$menu_grade."/".$menu_superior;       $i++;     }     my_menu($menu_content,$i,1,$menu_superior_temp);     /* 附数据库结构及模拟数据     # phpMyAdmin MySQL-Dump     #     # 主机: localhost 数据库 : test     # --------------------------------------------------------     #     # 数据表的结构 "menu"     #     CREATE TABLE menu (     menu_id int(11) NOT NULL auto_increment,     menu varchar(20) NOT NULL,     menu_grade int(11) NOT NULL,     menu_superior int(11) NOT NULL,     UNIQUE menu_id (menu_id)     );     #     # 导出下面的数据库内容 "menu"     #     INSERT INTO menu VALUES( "1", "计算机", "1", "0");     INSERT INTO menu VALUES( "2", "编程", "2", "1");     INSERT INTO menu VALUES( "3", "网络", "2", "1");     INSERT INTO menu VALUES( "4", "PHP与MySql", "3", "2");     INSERT INTO menu VALUES( "5", "C语言", "3", "2");     INSERT INTO menu VALUES( "6", "网页制作", "3", "3");     INSERT INTO menu VALUES( "7", "TCP、IP协议", "3", "3");     INSERT INTO menu VALUES( "8", "数学", "1", "0");     INSERT INTO menu VALUES( "9", "高等数学", "2", "8");     INSERT INTO menu VALUES( "10", "线性代数", "3", "9");     INSERT INTO menu VALUES( "11", "离散数学", "3", "9");     INSERT INTO menu VALUES( "12", "初等数学", "2", "8");     INSERT INTO menu VALUES( "13", "文学", "1", "0");     INSERT INTO menu VALUES( "14", "中国文学", "2", "13");     INSERT INTO menu VALUES( "15", "php", "4", "4");     INSERT INTO menu VALUES( "16", "mysql", "4", "4");   */   ?>