Execute PHP at different times on template page load

[SeanP]

So, in order to work around some broken (and possible security risking) functionality, that WHMCS insists is intended functionality, I have the need to execute PHP code at different times on the template page load of an addon module.  In the past, this could be accomplished by executing PHP code using the "{php}" tags at different places during the page load.  I basically need to execute PHP code at the start of the addon's template page load, then after the template page is fully loaded (at the end of the load).  How is this accomplished when using hooks to execute all of the PHP code?

[steven99]

Hooks are a bit limited when they come to changing templates. Some you can do a key-value pair and some you can do straight HTML.  What functionality are you trying to "fix" ?

[Kian]

You should provide more details. I tend to say that it's doable. As last resource you could use PHP stream (ob_start, ob_get_content) or auto prepend/append but don't do it, it sucks on so many levels and could break 3rd party modules.

Edited February 9, 2019 by Kian