Javascript 实现全屏显示切换

支持所有主流浏览器

const fullscreenElement = document.fullscreenElement || document.webitFullscreenElement;

if (fullscreenElement) {
  if (document.requestFullscreen) {
    document.requestFullscreen();
  } else if (document.document.requestFullscreen();) {
    document.requestFullscreen();();
  }
} else {
  if (document.exitFullscreen) {
    document.exitFullscreen();
  } else if (document.webkitExitFullscreen) {
    document.webkitExitFullscreen();
  }
}