PHP unlimited classification menu instance program

Recently, in a content management project, the customer has to come up with a multi-level classification. In fact, in many open-source backgrounds, there are infinite classification levels, such as the 111cn.net background, however, the data of these categories is only stored in one data table, and only associated with the source code.

The associated data is not complex. In fact, an excellent background design should be infinitely classified. In this way, you do not need to program the data separately during secondary development, as long as the function is the same, you can add a category in the background, so that the function is shared.

A simpler menu code for unlimited classification, I will simply implement the above principle. The key to this program is that the design of data tables is very distinctive and does not require recursion, you can use a simple SQL statement to list the menu and see how the data table is designed:

The database fields are roughly as follows:
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Id

Fid parent category ID

Name category name

Path classifier path, which uses id as a node to form a string similar to, 1, 2, 3, and 4.
----------------------------

The following data can be assumed:

Id fid name path
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1 0 Category 1, 1,

2 0 Category 2, 2,

3 1 classification 1-1, 1, 3,

4 1 classification 1-2, 1, 4,

5 2 categories 2-1, 2, 5,

6 4 categories 1-2-1, 1, 4, 6,
------------------
All the PHP code implemented is encapsulated in a class. It is not necessary, but I want to familiarize myself with OO !, Let's take a look at the page code:

The code is as follows:

Copy code

<? Php /************************************** Page: menu. php Author: www.111cn.net Function: defines database operations and generates menu lists. **************************************/ Class menu { // Create a constructor to connect to the database and select a database Public function _ construct (){ $ Dbhost = "localhost "; $ Dbuser = "root "; $ Dbpassword = "7529639 "; $ Dbname = "menu "; Mysql_connect ($ dbhost, $ dbuser, $ dbpassword) or die ("error! "); Mysql_query ("set names 'gbk '"); Mysql_select_db ($ dbname ); } // Execute SQL statement functions Private function query ($ SQL ){ Return mysql_query ($ SQL ); } // Obtain functions of the 111cn.net result set Private function loop_query ($ result ){ Return mysql_fetch_array ($ result ); } // List menu list functions Public function menulist (){ $ SQL = "select * from list order by path "; $ Result = $ this-> query ($ SQL ); While ($ rows = $ this-> loop_query ($ result )){ If (substr_count ($ rows ['path'], ',')> 2 ){ For ($ I = 0; $ I <(substr_count ($ rows ['path'], ',')-2); $ I ++) Echo ''; } Echo $ rows ['name']. '<br> '; } } // Create a destructor to disable database connection Public function _ destruct (){ Return mysql_close (); } } $ Db = new menu (); // Generate an instance $ Db-> menulist (); // call the method generation menu ?>

Tips: an infinitely classified menu is generated. Of course, the menu is not only applied to the menu, but also to the product category and the classification of the local and urban areas, to add, delete, modify, and query data in the background, you need to write it yourself.

Original article from: 04ie.com