vue exit/enter full screen

    handleScreen(data){
        let element = document.documentElement;
        // 判断是否已经是全屏
        // 如果是全屏，退出
        if (data == 'out') {
            if (document.exitFullscreen) {
                document.exitFullscreen();
            } else if (document.webkitCancelFullScreen) {
                document.webkitCancelFullScreen();
            } else if (document.mozCancelFullScreen) {
                document.mozCancelFullScreen();
            } else if (document.msExitFullscreen) {
                document.msExitFullscreen();
            }
        } else {    // 否则，进入全屏
            if (element.requestFullscreen) {
                element.requestFullscreen();
            } else if (element.webkitRequestFullScreen) {
                element.webkitRequestFullScreen();
            } else if (element.mozRequestFullScreen) {
                element.mozRequestFullScreen();
            } else if (element.msRequestFullscreen) {
                // IE11
                element.msRequestFullscreen();
            }
        }
    }