function onBeforeKeyDown(event) {
    var toggleKeys = 'SPACE|ENTER';
    var switchOffKeys = 'DELETE|BACKSPACE';
    var isKeyCode = (0, _function.partial)(_unicode.isKey, event.keyCode);

    if (!instance.getSettings().enterBeginsEditing && isKeyCode('ENTER')) {
      return;
    }

    if (isKeyCode("".concat(toggleKeys, "|").concat(switchOffKeys)) && !(0, _event.isImmediatePropagationStopped)(event)) {
      eachSelectedCheckboxCell(function () {
        (0, _event.stopImmediatePropagation)(event);
        event.preventDefault();
      });
    }

    if (isKeyCode(toggleKeys)) {
      changeSelectedCheckboxesState();
    }

    if (isKeyCode(switchOffKeys)) {
      changeSelectedCheckboxesState(true);
    }
  }
On before key down DOM listener.

@private
@param {Event} event