JS方法总结 - 控制浏览器全屏与退出全屏

function fullScreen() {
    // 判断是否处在全屏状态
    const isFullScreen = document.isFullScreen || document.mozIsFullScreen || document.webkitIsFullScreen;
    if (isFullScreen) {
         const el = document;
         let cfs = el.cancelFullScreen || el.mozCancelFullScreen || el.msExitFullscreen || el.webkitExitFullscreen || el.exitFullscreen;
          if (cfs) {
               cfs.call(el);
          } 
     } else {
          const el = document.documentElement;
          let rfs = el.requestFullScreen || el.webkitRequestFullScreen || el.mozRequestFullScreen || el.msRequestFullscreen;
          if (rfs) {
               rfs.call(el);
          }
     }
}

当使用F11进行全屏操作后，再点击按钮会无效，可以禁掉F11的全屏功能

        window.addEventListener('keydown', e => {
            // 阻止F11键默认事件，用HTML5全屏API代替
            e = e || window.event;
            if (e.keyCode === 122) {
                e.preventDefault();
                enterFullScreen();
            }
        });