html5横、竖屏状态 以及禁止横屏

<Meta name="screen-orientation" content="portrait"><!-- uc强制竖屏 -->
<Meta name="x5-orientation" content="portrait"><!-- QQ强制竖屏 -->

window.addEventListener("onorientationchange" in window ? "orientationchange" : "resize",hengshuping,false);

 function hengshuping() {
        if (window.orientation == 90 || window.orientation == -90) {
           //横屏
        } else {
            //竖屏
        }
    }