Heroselohim Heroselohim - 1 year ago 216
PHP Question

How to check if mcrypt extension exists on php

I would like to know the simplest and fastest PHP code line to check if mcrypt extension is available/installed.

There is a function that encrypts a string and first it requires to check if mcrypt is usable. If not, it will execute an alternative encrypt solution available on the system.

Thanks!

Answer Source

You can use function_exists to check if one of the mcrypt functions exists.

if(function_exists('mcrypt_encrypt')) {
    echo "mcrypt is loaded!";
} else {
    echo "mcrypt isn't loaded!";
}

Edit 30.07.2016:
Since my answer still gets a few upvotes from time to time, I benchmarked the performance of mine and Cristi Draghici's answers. The conclusion is, that function_exists is a bit faster than extension_loaded. https://3v4l.org/So4Ep