title: How to handle CTRL+PLUS key across browsers?
body: <p>I try to prevent the default zoom event and trigger a function instead.</p>
  
  <p>I managed to do it for the default save event (<kbd>CTRL</kbd>+<kbd>S</kbd>) across browsers:</p>
  
  <pre><code>document.documentElement.addEventListener('keydown', function(e) {
    e = e || window.event;
    var keynum;
    if (window.event) {
      keynum = e.keyCode;
    } else if (e.which) {
      keynum = e.which;
      if (e.ctrlKey) {
        switch (String.fromCharCode(keynum)) {
          case 'S':
            console.log('CTRL S pressed');
            e.preventDefault ? e.preventDefault() : (e.returnValue = false);
            break;
        }
      }
    }
  });
  </code></pre>
  
  <p><a href="https://codepen.io/anon/pen/NjRbaa?editors=1010" rel="nofollow noreferrer">https://codepen.io/anon/pen/NjRbaa?editors=1010</a></p>
  
  <p>However, <kbd>CTRL</kbd>+<kbd>+</kbd> seems more tricky since there is no cross browser <code>keyCode</code> for the "<code>+</code>" sign. I tried to use <code>keypress</code> instead of <code>keydown</code> but then the default isn't prevented in Chrome and IE.</p>