Return empty decrypt value

I want ask you, what happen if the password is not correct. I checked and noticed that in this way return empty string "", but I must be secure is this rule always valid? Because I need me to make compare if(decrypt(..)=="") then the password is incorect. Or data is compromised maybe.

Hi!.

The method decrypt() calls to openssl_decrypt() and mb_convert_encoding().

Function openssl_decrypt() returns FALSE on failure, and mb_convert_encoding() returns an empty string if the string being encoded is FALSE.

So, decrypt() returns an empty string if password is not valid and you can test with empty() or compare with "".

Thank you for your answer. :)