jquery让浏览器全屏

<button id="fullscreen-btn">进入全屏</button>

$(document).ready(function() {
    $('#fullscreen-btn').click(function() {
        var elem = document.documentElement; // 获取文档的根元素
        if (elem.requestFullscreen) {
            elem.requestFullscreen();
        } else if (elem.mozRequestFullScreen) { // Firefox
            elem.mozRequestFullScreen();
        } else if (elem.webkitRequestFullscreen) { // Chrome, Safari and Opera
            elem.webkitRequestFullscreen();
        } else if (elem.msRequestFullscreen) { // IE/Edge
            elem.msRequestFullscreen();
        }
    });
});

$(document).ready(function() {
    $('#exit-fullscreen-btn').click(function() {
        if (document.exitFullscreen) {
            document.exitFullscreen();
        } else if (document.mozCancelFullScreen) { // Firefox
            document.mozCancelFullScreen();
        } else if (document.webkitExitFullscreen) { // Chrome, Safari and Opera
            document.webkitExitFullscreen();
        } else if (document.msExitFullscreen) { // IE/Edge
            document.msExitFullscreen();
        }
    });
});