[dowster]

you would want to read through the ban file and compare the lines to the name/ip and if it gets a hit then ban them.
Go to the wiki and look for some topics about how to read files.
Here's some links if you'r too lazy to search. (Not saying your a lazy person, we all get lazy at times :P)
https://sampwiki.blast.hk/wiki/Fclose
https://sampwiki.blast.hk/wiki/Fread
https://sampwiki.blast.hk/wiki/Fopen