international-keyboard-handling.js

// From: https://hacks.mozilla.org/2017/03/internationalize-your-keyboard-controls/

window.addEventListener('keydown', function(e) {
  if (e.defaultPrevented) {
    return;
  }

  // We don't want to mess with the browser's shortcuts
  if (e.ctrlKey || e.altKey || e.metaKey || e.shiftKey) {
    return;
  }

  // We try to use `code` first because that's the layout-independent property.
  // Then we use `key` because some browsers, notably Internet Explorer and
  // Edge, support it but not `code`. Then we use `keyCode` to support older
  // browsers like Safari, older Internet Explorer and older Chrome.
  switch (e.code || e.key || e.keyCode) {
    case 'KeyW': // This is 'W' on QWERTY keyboards, but 'Z' on AZERTY keyboards
    case 'KeyI':
    case 'ArrowUp':
    case 'Numpad8':
    case 38: // keyCode for arrow up
      changeDirectionUp();
      break;
   
    // ... Other letters: ASD, JKL, arrows, numpad

    default:
      return;
  }

  e.preventDefault();
  doSomethingUseful();
});

// touch handling
// A real implementation would want to use touchstart and touchend as well.
window.addEventListener('touchmove', function(e) {
  // don't forget to throttle the event
});