Yeah, I'm building a software for practice in php and mysqli.
So I wanna know methods for max protection as it's most important thing when you are working with php. I'm building it from scratch so yeah, I'm using what I found on most of sites... And that's what I posted in first post.
I'm from Croatia, yes, so we have letters like č,ć,ž,đ,š... I'll check difference between those htmlentities and this what I'm using now, thanks :)
Also, because it's "software", yes, there is a lot of things that are going to database and showing on site. So I'm using this code I posded and ifs for each input to check if it's filled... Right now I'm not validating inputs, I will do that next.