If your cat is difficult to catch, there's no way you're getting him into a cat carrier without over stressing him and yourself. When he is eating throw a old unwanted throw over him, make sure as you pick him up, tuck the throw tightly around him so his limbs are less mobile and he can't wriggle himself out. Be sure to have a good size box nearby to immediately put him in. Leave the throw in with him (unwrap him of course) so he doesn't slide around in the box on the way to the vet. Yes he will be stressed and shed a lot of hair, but you've got to do what you've got to do for the sake of his health. Make sure the box has breathing holes.
hi and welcome to our forum. your kitty really needs to get to a Vet sounds like he has uveitis which is not only very painful but will also lead to blindness. I will send you a link to click on and read more about...please help him out asap
http://www.medicinenet.com/pets/cat-health/eye_infections_or_uveitis_in_cats.htm