var supportsOrientationChange = "onorientationchange" in window,
  orientationEvent = supportsOrientationChange ? "orientationchange" : "resize";
// 监听事件
window.addEventListener(orientationEvent, function () {
  var ua = navigator.userAgent;
  var deviceType = "";
  //判断设备类型 
  if (ua.indexOf("iPad") > 0) {
    deviceType = "isIpad";
  } else if (ua.indexOf("Android") > 0) {
    deviceType = "isAndroid";
  } else {
    //  console.log("既不是ipad，也不是安卓！");
    return;
  }
  let ipadId = document.getElementById('orientLayer')
  // 判断横竖屏 
  if ("isIpad" == deviceType) {
    if (Math.abs(window.orientation) == 90) {
      ipadId.style.display = 'block'
      // console.log("我是ipad的横屏",ipadId.style.display = 'block');
    } else {
      // console.log("我是ipad的竖屏");
      ipadId.style.display = 'none'
    }
  }
}, false);