This is the easiest way to detect if your smartphone (Android, iPhone, …) or tablet device (iPad, Galaxy Tab, …) is in portrait mode or landscape mode:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 | function doOnOrientationChange() { switch(window.orientation) { case -90: case 90: alert('landscape'); break; default: alert('portrait'); break; } } window.onorientationchange = function() { doOnOrientationChange(); }; // Initial execution doOnOrientationChange(); |
The code also detects if the screen orientation has changed.