PHP unlimited classification program_PHP tutorial

I have often introduced the issue of infinite classification in the past. In most cases, we use PHP recursion to achieve it. The infinite classification introduced today does not require recursion. The method is very simple and friends in need can refer to it.

The code is as follows

Copy code

/////////////// //////Infinitely classified database design and examples ////////////// mysql> create database db_kind; Query OK, 1 row affected mysql> use db_kind; Database changed mysql> create table tb_kind( -> id int not null auto_increment primary key, -> pid int, -> path varchar(200) -> ); Query OK, 0 rows affected mysql> insert into tb_kind values(null,"news",0,0); Query OK, 1 row affected mysql> insert into tb_kind values(null,"video",0,0); Query OK, 1 row affected mysql> insert into tb_kind values(null,"picture",0,0); Query OK, 1 row affected mysql> insert into tb_kind values(null,"Blog",0,0); Query OK, 1 row affected mysql> insert into tb_kind values(null,"Sports News",1,"0-1"); Query OK, 1 row affected mysql> insert into tb_kind values(null,"Entertainment News",1,"0-1"); Query OK, 1 row affected mysql> insert into tb_kind values(null,"Financial News",1,"0-1"); Query OK, 1 row affected mysql> select * from db_kind; ERROR 1146: Table 'db_kind.db_kind' does not exist mysql> select * from tb _kind; +----+----------+-----+------+ | id | pname | pid | path | +----+----------+-----+------+ | 1 | News | 0 | 0 | | 2 | Video | 0 | 0 | | 3 | Pictures | 0 | 0 | | 4 | Blog | 0 | 0 | | 5 | Sports News | 1 | 0-1 | | 6 | Entertainment News | 1 | 0-1 | | 7 | Financial News | 1 | 0-1 | +----+----------+-----+------+ 7 rows in set mysql> insert into tb_kind values(null,"Basketball News",5,"0-1-5"); Query OK, 1 row affected mysql> insert into tb_kind values(null,"Football News",5,"0-1-5"); Query OK, 1 row affected mysql> select * from tb_kind; +----+----------+-----+-------+ | id | pname | pid | path | +----+----------+-----+-------+ | 1 | News | 0 | 0 | | 2 | Video | 0 | 0 | | 3 | Pictures | 0 | 0 | | 4 | Blog | 0 | 0 | | 5 | Sports News | 1 | 0-1 | | 6 | Entertainment News | 1 | 0-1 | | 7 | Financial News | 1 | 0-1 | | 8 | Basketball News | 5 | 0-1-5 | | 9 | Football News | 5 | 0-1-5 | +----+----------+-----+-------+ 9 rows in set mysql> insert into tb_kind values(null,"NBA",8,"0-1-5-8"); Query OK, 1 row affected mysql> insert into tb_kind values(null,"CBA",8,"0-1-5-8"); Query OK, 1 row affected mysql> select * from tb_kind; +----+----------+-----+---------+ | id | pname | pid | path | +----+----------+-----+---------+ | 1 | News | 0 | 0 | | 2 | Video | 0 | 0 | | 3 | Pictures | 0 | 0 | | 4 | Blog | 0 | 0 | | 5 | Sports News | 1 | 0-1 | | 6 | Entertainment News | 1 | 0-1 | | 7 | Financial News | 1 | 0-1 | | 8 | Basketball News | 5 | 0-1-5 | | 9 | Football News | 5 | 0-1-5 | | 10 | NBA | 8 | 0-1-5-8 | | 11 | CBA | 8 | 0-1-5-8 | +----+----------+-----+---------+ 11 rows in set mysql> select concat(path,"-",id) from tb_kind; +---------------------+ | concat(path,"-",id) | +---------------------+ | 0-1 | | 0-2 | | 0-3 | | 0-4 | | 0-1-5 | | 0-1-6 | | 0-1-7 | | 0-1-5-8 | | 0-1-5-9 | | 0-1-5-8-10 | | 0-1-5-8-11 | +---------------------+ 11 rows in set mysql> select concat(path,"-",id) from tb_kind; +---------------------+ | concat(path,"-",id) | +---------------------+ | 0-1 | | 0-2 | | 0-3 | | 0-4 | | 0-1-5 | | 0-1-6 | | 0-1-7 | | 0-1-5-8 | | 0-1-5-9 | | 0-1-5-8-10 | | 0-1-5-8-11 | +---------------------+ 11 rows in set mysql> select concat(path,"-",id) as abs from tb_kind order by abs.path; ERROR 1054 : Unknown column 'abs.path' in 'order clause' mysql> select concat(path,"-",id) as abs from tb_kind order by abs +------------+ | abs | +------------+ | 0-1 | | 0-1-5 | | 0-1-5-8 | | 0-1-5-8-10 | | 0-1-5-8-11 | | 0-1-5-9 | | 0-1-6 | | 0-1-7 | | 0-2 | | 0-3 | | 0-4 | +------------+ 11 rows in set mysql> select concat(path,"-",id) as,id,name,path abs from tb_kind order by abs; ERROR 1064 : You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'id,name,path abs from tb_kind order by abs' at line 1 mysql> select concat(path,"-",id) as abs, id,pname,path abs from tb_kind order by abs; +------------+----+----------+---------+ | abs | id | pname | abs | +------------+----+----------+---------+ | 0-1 | 1 | 新闻 | 0 | | 0-1-5 | 5 | 体育新闻 | 0-1 | | 0-1-5-8 | 8 | 篮球新闻 | 0-1-5 | | 0-1-5-8-10 | 10 | NBA | 0-1-5-8 | | 0-1-5-8-11 | 11 | CBA | 0-1-5-8 | | 0-1-5-9 | 9 | 足球新闻 | 0-1-5 | | 0-1-6 | 6 | 娱乐新闻 | 0-1 | | 0-1-7 | 7 | 财经新闻 | 0-1 | | 0-2 | 2 | 视频 | 0 | | 0-3 | 3 | 图片 | 0 | | 0-4 | 4 | 博客 | 0 | +------------+----+----------+---------+ 11 rows in set mysql> php处理分类源码 $conn=mysql_connect("localhost","root","root"); mysql_select_db("db_kind"); mysql_query("set names utf8"); $sql="select concat(path,'-',id) as abspath,id,pname,path from tb_kind order by abspath"; $rs=mysql_query($sql); while($result=mysql_fetch_assoc($rs)){ $num=count(explode("-",$result[path]))-1; $new_str=str_repeat("---",$num); echo $new_str.$result[pname]; echo " "; } $str=str_repeat("=",10); echo $str; $num=count(explode("-","0-1-5-8"))-1; echo $num; ?>

http://www.bkjia.com/PHPjc/631691.htmlwww.bkjia.comtruehttp://www.bkjia.com/PHPjc/631691.htmlTechArticle以前也经常介绍关于无限分类这个问题，大多数情况我们都是利用php递归来实现，今天介绍的这篇无限分类不需要递归哦，方法很简单有需...