//判断手机横竖屏状态：
window.addEventListener("onorientationchange" in window ? "orientationchange" : "resize", function() {
  if (window.orientation === 180 || window.orientation === 0) {
    //竖屏
  }
  if (window.orientation === 90 || window.orientation === -90 ){
    //横屏
  }
}, false);

判断手机横竖屏