How to track two key presses at the same time?

Question

JavaScript

When you press one key, hold it down, a handler is executed, and during this you need to press another key and another handler will work once so that after it is completed, tracking of the previous button is continued.
In general, you need to do something similar to the events in games, when the hero can move and when you press the button, he jumps, but does not stop moving

Answer 1

First, you can use this plugin .
Secondly, as far as I know, it is impossible (so at the system level) to track the pressing of two buttons of the same type, for example H + L. For example, my keyboard does not respond to such combinations at all. If you need to track hotkeys, then here is an example from the Internet

function keydown(evt){
  if (!evt) evt = event;
  if (evt.ctrlKey && evt.altKey && evt.keyCode==115){ //CTRL+ALT+F4
    alert("CTRL+ALT+F4"); 
  }
  else if (evt.shiftKey && evt.keyCode == 9){ //Shif+TAB
    alert("Shift+TAB");
  }
}