AlksAlena

componentDidMount() {
  document.body.addEventListener("keydown", this.escClosePopup);
}
componentWillUnmount() {
  document.body.removeEventListener("keydown", this.escClosePopup);
}
escClosePopup() { // press Escape key
  if (event.keyCode == 27) {
    this.closePopup();
  }

AlksAlena

var cmdDown = false;

document.body.addEventListener('keydown', function(event) {
  var key = event.keyCode || event.charCode || 0;
  if ([91,93,224,17].indexOf(key) !== -1) {
    cmdDown = true;
  }
  console.log('CMD DOWN: ' + cmdDown.toString());    
});