How can I tell if an event comes from right Ctrl key?

Question

I have an event listener in Javascript, I can tell whether a key event is Ctrl (e.keyCode == 17), but how can I know this Ctrl comes from the right one or left

Answer 1

There is event.location property for left ctrl key it will be 1 for right one 2, you can check browser support on canIuse

if (e.which == 17) {
   if (event.location == 1) {
      // left ctrl key
   } else if (event.location == 2) {
      // right ctrl key
   }
}