[Dayrion]

You can use strcmp (called str(->ing)cmp(->comparision)). Take a look on the wiki for futher details : https://sampwiki.blast.hk/wiki/Strcmp
A basically example:

PHP Code:

if(strcmp("hey", string) == 0)
... 


If you want to compare 2 caracter, which is not the same thing, you need to compare the ASCII code of those 2 characters (All character there: http://www.ascii-code.com/).