event.key is undefined in mobile browsers for keyup, keydown and keypress

Question

The following code is supposed to simply suppress any key press and add the pressed key to a div instead. This works fine on desktop, however on mobile (safari and chrome) <

Answer 1

The only workaround is to get the keycode and cast it to String:

var str = '';
var el = document.getElementById('#test');
document.addEventListener('keypress', function(event) {
  const currentCode = event.which || event.code;
  let currentKey = event.key;
  if (!currentKey) {
    currentKey = String.fromCharCode(currentCode);
  }
  str += currentKey;
  event.preventDefault();
  el.innerHTML = str;
})