一、全屏

// 找到适合浏览器的全屏方法
function launchFullScreen(element) {  if(element.requestFullScreen) {  element.requestFullScreen();  } else if(element.mozRequestFullScreen) {  element.mozRequestFullScreen();  } else if(element.webkitRequestFullScreen) {  element.webkitRequestFullScreen();  }
}  // 启动全屏模式
launchFullScreen(document.documentElement); // the whole page
launchFullScreen(document.getElementById("videoElement")); // any individual element  

二、页面可见性：判断用户是否正在浏览

// 设置隐藏属性和可见改变事件的名称，属性需要加浏览器前缀
// since some browsers only offer vendor-prefixed support
var hidden, state, visibilityChange;
if (typeof document.hidden !== "undefined") {  hidden = "hidden";  visibilityChange = "visibilitychange";  state = "visibilityState";
} else if (typeof document.mozHidden !== "undefined") {  hidden = "mozHidden";  visibilityChange = "mozvisibilitychange";  state = "mozVisibilityState";
} else if (typeof document.msHidden !== "undefined") {  hidden = "msHidden";  visibilityChange = "msvisibilitychange";  state = "msVisibilityState";
} else if (typeof document.webkitHidden !== "undefined") {  hidden = "webkitHidden";  visibilityChange = "webkitvisibilitychange";  state = "webkitVisibilityState";
}  // 添加一个标题改变的监听器
document.addEventListener(visibilityChange, function(e) {  // 开始或停止状态处理
}, false);  

三、使用麦克风和摄像头

// 设置事件监听器
window.addEventListener("DOMContentLoaded", function() {  // 获取元素  var canvas = document.getElementById("canvas"),  context = canvas.getContext("2d"),  video = document.getElementById("video"),  videoObj = { "video": true },  errBack = function(error) {  console.log("Video capture error: ", error.code);   };  // 设置video监听器  if(navigator.getUserMedia) { // Standard  navigator.getUserMedia(videoObj, function(stream) {  video.src = stream;  video.play();  }, errBack);  } else if(navigator.webkitGetUserMedia) { // WebKit-prefixed  navigator.webkitGetUserMedia(videoObj, function(stream){  video.src = window.webkitURL.createObjectURL(stream);  video.play();  }, errBack);  }
}, false);  

四、电池

var battery = navigator.battery || navigator.webkitBattery || navigator.mozBattery;  // 电池属性
console.warn("Battery charging: ", battery.charging); // true
console.warn("Battery level: ", battery.level); // 0.58
console.warn("Battery discharging time: ", battery.dischargingTime);  // 添加事件监听器
battery.addEventListener("chargingchange", function(e) {  console.warn("Battery charge change: ", battery.charging);
}, false);

五、prefetch预先加载

<!-- full page -->
<link rel="prefetch" href="http://davidwalsh.name/css-enhancements-user-experience" />  <!-- just an image -->
<link rel="prefetch" href="http://davidwalsh.name/wp-content/themes/walshbook3/images/sprite.png" />