全屏

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;
}

退出全屏  

function exitScreen(){
    if (document.exitFullscreen) { 
        document.exitFullscreen(); 
    } 
    else if (document.mozCancelFullScreen) { 
        document.mozCancelFullScreen(); 
    } 
    else if (document.webkitCancelFullScreen) { 
        document.webkitCancelFullScreen(); 
    } 
    else if (document.msExitFullscreen) { 
        document.msExitFullscreen(); 
    }
    if(typeof cfs != "undefined" && cfs) {
        cfs.call(el);
    }
}

ie低版本的全屏，退出全屏都这个方法

function iefull(){
    var el = document.documentElement;
    var rfs =  el.msRequestFullScreen;
    if(typeof window.ActiveXObject != "undefined") {
        //这的方法 模拟f11键，使浏览器全屏
        var wscript = new ActiveXObject("WScript.Shell");
        if(wscript != null) {
            wscript.SendKeys("{F11}");
        }
    }
}

注：ie调用ActiveX控件，需要在ie浏览器安全设置里面把 ‘未标记为可安全执行脚本的ActiveX控件初始化并执行脚本’ 设置为启用

链接: https://www.fly63.com/article/detial/2034