title: javascript - calculate "true" keyCode
body: <p>When I press a key on my keyboard, I can get the keyCode of that key using e.keyCode. But the keyCode I get does not consider the pressed alt/ctrl/shift keys, wich modify the key code.</p>
  
  <p>Fortunately, I get the properties shiftKey/altKey/ctrlKey with the event so I am able to calculate the "true" key code.</p>
  
  <p>But I don't know how to calculate this correctly. Where can I read about that?
  Is it as easy as substracting 32 if shift ist pressed and so on, or are there much exceptions?</p>