js判断网页是否全屏

下面是原文
https://blog.csdn.net/k358971707/article/details/60465689
这里直接上结果

         function isFullscreenForNoScroll(){
            var explorer = window.navigator.userAgent.toLowerCase();
            if(explorer.indexOf('chrome')>0){//webkit
                if (document.body.scrollHeight === window.screen.height && document.body.scrollWidth === window.screen.width) {
                    alert("全屏");
                } else {
                    alert("不全屏");
                }
            }else{//IE 9+  fireFox
                if (window.outerHeight === window.screen.height && window.outerWidth === window.screen.width) {
                    alert("全屏");
                } else {
                    alert("不全屏");
                }
            }
        }