移动端判断横屏竖屏

1. CSS判断横屏竖屏

写在同一个CSS中

@media screen and (orientation: portrait) {
　　/*竖屏 css*/
}
@media screen and (orientation: landscape) and (min-width:450px){
　　/*横屏 css*/
}
分开写在2个CSS

竖屏
<link rel="stylesheet" media="all and (orientation:portrait)" href="portrait.css">

横屏
<link rel="stylesheet" media="all and (orientation:landscape)" href="landscape.css">

2. JS判断横屏竖屏

var sEvent = "onorientationchange" in window ? "orientationchange" : "resize";
window.addEventListener(sEvent, function() {
    if (window.orientation === 180 || window.orientation === 0) { 
        alert('竖屏状态！');
    } 
    if (window.orientation === 90 || window.orientation === -90 ){ 
        alert('横屏状态！');
    }  
}, false);