location.host vs location.hostname and cross-browser compatibility?

Question

Which one of these is the most effective vs checking if the user agent is accessing via the correct domain.

We would like to show a small js based \'top bar\' style

Answer 1

If you are insisting to use the window.location.origin You can put this in top of your code before reading the origin

if (!window.location.origin) {
  window.location.origin = window.location.protocol + "//" + window.location.hostname + (window.location.port ? ':' + window.location.port: '');
}

Solution

PS: For the record, it was actually the original question. It was already edited :)