放大：myVideo.webkitRequestFullScreen();
    缩小：document.webkitCancelFullScreen();
    这些方法是不全面的，仅限于谷歌浏览器

    1. //进入全屏
    2. function FullScreen() {
    3.     var ele = document.documentElement;
    4.     if (ele.requestFullscreen) {
    5.         ele.requestFullscreen();
    6.     } else if (ele.mozRequestFullScreen) {
    7.         ele.mozRequestFullScreen();
    8.     } else if (ele.webkitRequestFullScreen) {
    9.         ele.webkitRequestFullScreen();
    10.     }
    11. }
    13. //退出全屏
    14. function exitFullscreen() {
    15.     var de = document;
    16.     if (de.exitFullscreen) {
    17.         de.exitFullscreen();
    18.     } else if (de.mozCancelFullScreen) {
    19.         de.mozCancelFullScreen();
    20.     } else if (de.webkitCancelFullScreen) {
    21.         de.webkitCancelFullScreen();
    22.     }
    23. }