I've been getting logs in my error log, which I've tracked down to be a problem with bad characters being send as URL parameters. My problem is that i don't know how to detect those in my code to be able to return a proper error message.
This is the parameter that is making a mess:
%E2%80%A2%C2%B0$%CallmeG.G%25$%C2%B0%E2%80%A2&name%5B35%5D
After urldecoding, this will be:
•°$�llmeG.G%$°•
I can see that something goes wrong here with the "�". Which is the only character messing up my code. However I am not sure how to detect this or help the problem.
If you
urldecode('%Ca');
the output is
�
You need to remove (or escape) the '%' preceding 'Ca'.