[转载]你可能不知道的5个功能强大的 HTML5 API —— html5系列

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// 根据目标元素调用相应的方法

function launchFullScreen(element) {

  if(element.requestFullScreen) {

    element.requestFullScreen();

  } else if(element.mozRequestFullScreen) {

    element.mozRequestFullScreen();

  } else if(element.webkitRequestFullScreen) {

    element.webkitRequestFullScreen();

  }

}

// 在支持的浏览器中启动全屏

launchFullScreen(document.documentElement); // 整个页面

launchFullScreen(document.getElementById("videoElement")); // 单个元素

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// 部分浏览器只支持 vendor-prefixed

// 根据浏览器支持情况设置隐藏属性和可见状态改变事件

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";

}

// 添加一个时间来实时改变页面的标题

document.addEventListener(visibilityChange, function(e) {

  // Start or stop processing depending on state

}, false);

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// 添加事件监听器

window.addEventListener("DOMContentLoaded", function() {

  // 获取元素，创建配置

  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);

    };

  // 添加视频监听器

  if(navigator.getUserMedia) { // 标准的API

    navigator.getUserMedia(videoObj, function(stream) {

      video.src = stream;

      video.play();

    }, errBack);

  } else if(navigator.webkitGetUserMedia) { // WebKit 核心的API

    navigator.webkitGetUserMedia(videoObj, function(stream){

      video.src = window.webkitURL.createObjectURL(stream);

      video.play();

    }, errBack);

  }

}, false);

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// 获取电池对象

var battery = navigator.battery || navigator.webkitBattery || navigator.mozBattery;

// 一组非常有用的电池属性

console.warn("Battery charging: ", battery.charging); // true

console.warn("Battery level: ", battery.level); // 0.58

console.warn("Battery discharging time: ", battery.dischargingTime);

// 监听电池状态

battery.addEventListener("chargingchange", function(e) {

  console.warn("Battery charge change: ", battery.charging);

}, false);

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