前提

公司大屏展示的系统总是要费很大劲去拖动笨拙的鼠标去达到全屏显示

export function fullscreen(){
    var el = document.documentElement;
    var rfs = el.requestFullScreen || el.webkitRequestFullScreen || el.mozRequestFullScreen || el.msRequestFullScreen;
    if(typeof rfs != "undefined" && rfs) {
        rfs.call(el);
    };
    return;
}