H5点击按钮，实现浏览器全屏模式代码

<button class="fullBtn">点击实现全屏</button>

$(‘.fullBtn‘).on(‘click‘, function() {

         var docElm = document.documentElement;

         // W3C         if (docElm.requestFullscreen) {            docElm.requestFullscreen();         }         // FireFox         else if (docElm.mozRequestFullScreen) {            docElm.mozRequestFullScreen();         }         // Chrome等         else if (docElm.webkitRequestFullScreen) {            docElm.webkitRequestFullScreen();         }         // IE11         else if (elem.msRequestFullscreen) {            elem.msRequestFullscreen();         }      });