兼容火狐、谷歌、IE11及以上浏览器

//全屏显示

launchFullscreen(element) {

  if(element.requestFullscreen) {

    element.requestFullscreen();

  } else if(element.mozRequestFullScreen) {

    element.mozRequestFullScreen();

  } else if(element.webkitRequestFullscreen) {

    element.webkitRequestFullscreen();

  } else if(element.msRequestFullscreen) {

    element.msRequestFullscreen();

  }

},

// 退出全屏

exitFullscreen () {

  if(document.exitFullscreen) {

    document.exitFullscreen();

  } else if(document.mozCancelFullScreen) {

    document.mozCancelFullScreen();

  } else if(document.webkitExitFullscreen) {

    document.webkitExitFullscreen();

  }

},

//监听全屏状态，全屏返回dom，否则返回false

watchFullScreen(){

  document.addEventListener("fullscreenchange", function () { 

          var isFull = document.fullscreenElement    ||

                  document.msFullscreenElement  ||

                  document.mozFullScreenElement ||

                  document.webkitFullscreenElement || false;

    }, false); 

    document.addEventListener("mozfullscreenchange", function () {

         var isFull = document.fullscreenElement    ||

                  document.msFullscreenElement  ||

                  document.mozFullScreenElement ||

                  document.webkitFullscreenElement || false;

    }, false); 

    document.addEventListener("webkitfullscreenchange", function () { 

           var isFull = document.fullscreenElement    ||

                  document.msFullscreenElement  ||

                  document.mozFullScreenElement ||

                  document.webkitFullscreenElement || false;

    }, false); 

    document.addEventListener("msfullscreenchange", function () { 

          var isFull = document.fullscreenElement    ||

                  document.msFullscreenElement  ||

                  document.mozFullScreenElement ||

                  document.webkitFullscreenElement || false;

    }, false);

},