inArray-like check for event.which

gistfile1.txt

var which = event.which; // or whatever defines `which`
var chars = [1, 2, 3, 4];

if (iPressedOneOfThese(chars)) {
  // Do my stuff
}

function iPressedOneOfThese(array) {
  array.filter(chars, function (char) {
    return which === char;
  }).length
}