js实现Html网页全屏效果

 //全屏
        function toggleFullScreen() {
            if (!document.fullscreenElement && // alternative standard method
                !document.mozFullScreenElement && !document.webkitFullscreenElement) {// current working methods
                if (document.documentElement.requestFullscreen) {
                    document.documentElement.requestFullscreen();
                } else if (document.documentElement.mozRequestFullScreen) {
                    document.documentElement.mozRequestFullScreen();
                } else if (document.documentElement.webkitRequestFullscreen) {
                    document.documentElement.webkitRequestFullscreen(Element.ALLOW_KEYBOARD_INPUT);
                }
            } else {
                if (document.cancelFullScreen) {
                    document.cancelFullScreen();
                } else if (document.mozCancelFullScreen) {
                    document.mozCancelFullScreen();
                } else if (document.webkitCancelFullScreen) {
                    document.webkitCancelFullScreen();
                }
            }
        }

直接调用即可：

<button onclick="toggleFullScreen()">全屏模式</button>