if you want to sort the extensions from a to z the easiest way is to use natcasesort.
(PHP 4, PHP 5)
get_loaded_extensions — Returns an array with the names of all modules compiled and loaded
$zend_extensions= false ] )
This function returns the names of all the modules compiled and loaded in the PHP interpreter.
Only return Zend extensions, if not then regular extensions, like mysqli are listed. Defaults to
FALSE(return regular extensions).
Returns an indexed array of all the modules names.
Example #1 get_loaded_extensions() Example
The above example will output something similar to:
Array (  => xml  => wddx  => standard  => session  => posix  => pgsql  => pcre  => gd  => ftp  => db  => calendar  => bcmath )
I was not sure of the Zend extensions. and no zend extensions was coming on my installation. print_r(get_loaded_extensions(true)); print zend extensions loaded.
To know the zend extensions loaded in you installation, use phpinfo() and check where it says "This program makes use of ...". It is the third section in output.
If you have Xdebug installed and enabled then this is a zend extension and it will be listed there.