Dynamically generate level-2 menus

Nowadays, more and more level-2 or even multi-level menus are used, and the display and manual designation of foreground menus are increasingly insufficient. Therefore, dynamic Menu Generation is required.

Idea + sample code (take level-2 menu as an example)

First, retrieve the level-1 menu content value. Next, traverse the level-1 menu and use its ID as the parentid of this search. Then, obtain the level-2 menu value corresponding to it,

And add it to the current array (background)

Layer-2 loop. When a value is obtained, check whether there is data for the level-2 menu items. If there is data, the output will be returned. If not, skip (foreground)

Take the PHP background as an Example

$ Res = mysql_query ('*** where parentid = 0'); // obtain the first-level menu content

Foreach ($ res as & $ V)

{

. $ Tres = mysql_query ('*** where parentid ='. $ V ['id']);

$ V ['T'] = $ tres;

}

Front-end

<? PHP if ($ res! = NULL):?>

<? PHP foreach ($ res as $ Val):?>

<Li> outer HTML tag </LI>

<Ul>

<? PHP if ($ res! = NULL):?>

<? PHP foreach ($ res as $ Val):?>

<Li> layer-4 HTML tag </LI>

<? PHP endforeach;?>
<? PHP endif;?>

</Ul>

<? PHP endforeach;?>

<? PHP endif;?>

If you have different opinions, you are welcome to raise them.

Dynamically generate level-2 menus