keydown checks on two keys at once

[sssssssssss]

PHP Code:

if (keydown(0) && keydown(1)) {
            player.x + 1;
            player.y + 1;
          } 


This isn't working, but I need to know if there is a way to check if, say you had pressed up, and was holding it, then pressed right, and do something with that combination. This is during a freezeplayer too.