[Developer]

[How-to] Hooks and Plugins


In hooks_vbulletin.xml you will see things like the following:
Code:

PHP Code:

<hooktype type="general">
        <hook>global_start</hook>
        <hook>global_complete</hook>


The hooktype is just a unigue name for the hook tags within. The hook tags refer specifically to PHP code in the vB files.

The PHP code in the vB files looks like the following:
Code:

PHP Code:

($hook = vBulletinHook::fetch_hook('global_start')) ? eval($hook) : false;


Note how global_start is in a hook tag in hooks_vbulletin.xml and also in the vB PHP code.

To make a plugin hooked to global.php, you create an XML file as follows:
Code:

PHP Code:

<?xml version="1.0" encoding="ISO-8859-1"?>

<plugins>
    <plugin active="1" devkey="Name" product="vbulletin">
        <title>Your Title</title>
        <hookname>global_start</hookname>
        <phpcode><![CDATA[//
// START PHP CODE

$foo = "bar";

// END PHP CODE
//]]></phpcode>
    </plugin>
</plugins>

The place in vB PHP code where your global_start plugin runs is where the following occurs in global.php:
Code:

PHP Code:

($hook = vBulletinHook::fetch_hook('global_start')) ? eval($hook) : false;


Basically, you make plugins via XML and your plugins hook to vB PHP code
via <hookname>hook_name</hookname> from the plugins,
which needs to match the fetch_hook('hook_name') in the vB PHP code,
which needs to match <hook>hook_name</hook> in hooks_vbulletin.xml.

You can even make a plugin that hooks to multiple vB PHP files as follows:
Code:

PHP Code:

<?xml version="1.0" encoding="ISO-8859-1"?>

<plugins>
    <plugin active="1" devkey="Name1" product="vbulletin">
        <title>Your Title1</title>
        <hookname>global_start</hookname>
        <phpcode><![CDATA[//
// START PHP CODE1

$foo = "bar";

// END PHP CODE1
//]]></phpcode>
    </plugin>
    <plugin active="1" devkey="Name2" product="vbulletin">
        <title>Your Title2</title>
        <hookname>forumhome_start</hookname>
        <phpcode><![CDATA[//
// START PHP CODE2

$bar = "foo";

// END PHP CODE2
//]]></phpcode>
    </plugin>
</plugins>

This latter example runs the first batch of PHP code where the following occurs in global.php:
Code:

PHP Code:

($hook = vBulletinHook::fetch_hook('global_start')) ? eval($hook) : false;


And runs the second batch of PHP code where the following occurs in index.php:
Code:

PHP Code:

($hook = vBulletinHook::fetch_hook('forumhome_start')) ? eval($hook) : false;


Again, note how <hookname>hook_name</hookname> in the XML plugin
matches fetch_hook('hook_name') in the vB PHP code
matches <hook>hook_name</hook> in hooks_vbulletin.xml.

[Developer]

What is a hook

PHP Code:

http://forum.egypt.com/enforum/articles-f145/what-hook-3856.html