Link Encrypt

Is there any way to know, if the link is already encrypted?
I tried this method : https://jehy.ru/articles/2014/12/09/encrypting-links-for-wp-noexternallinks/

And clear all the cache but there are no different between before I encrypt the link and after I encrypt the link.

Also, does the custom parser automatically chosen after I create the files? Cause there are no information regarding this, on the guide.

Thanks