Why Editor reformats my code

Question

I'm using TinyMCE Advanced and SyntaxHighliter plugins on my WordPress install.

Why does the editor change my inserted code, from:

[php]
<?php
/**
echo('code');
/**/
[/php]

to:

[php]
<!--?php <br ?-->/**
echo('code');
/**/
[/php]

Answer 1

I suggest you to use htmlspecialchars() before sending content andhtmlspecialchars_decode() before showing content on page, here is functions that you need to copy/paste to your functions.php :

function wp_po9568($content)
{
    return htmlspecialchars($content);
}
add_filter('content_save_pre','wp_po9568');

And:

function wp_po5689($content)
{
    return htmlspecialchars_decode($content);
}
add_filter( 'the_content','wp_po5689');

Wordpress by default comments out php tags.

Answer 2

You can use this filter on your theme functions.php

remove_filter( 'the_content', 'wpautop' );
add_filter( 'the_content', 'wpautop' , 12);

This will remove extra P and line brake from short-code. More details will found here http://dynamicweblab.com/2012/10/removing-extra-p-and-line-breaks-from-shortcodes-in-wordpress/