是否有可能在JavaScript中检测“空闲”时间?
我的主要用例可能是预取或预加载内容。
我将空闲时间定义为用户不活动或没有任何CPU使用的时间段
当前回答
根据equiman提供的输入:
class _Scheduler {
timeoutIDs;
constructor() {
this.timeoutIDs = new Map();
}
addCallback = (callback, timeLapseMS, autoRemove) => {
if (!this.timeoutIDs.has(timeLapseMS + callback)) {
let timeoutID = setTimeout(callback, timeLapseMS);
this.timeoutIDs.set(timeLapseMS + callback, timeoutID);
}
if (autoRemove !== false) {
setTimeout(
this.removeIdleTimeCallback, // Remove
10000 + timeLapseMS, // 10 secs after
callback, // the callback
timeLapseMS, // is invoked.
);
}
};
removeCallback = (callback, timeLapseMS) => {
let timeoutID = this.timeoutIDs.get(timeLapseMS + callback);
if (timeoutID) {
clearTimeout(timeoutID);
this.timeoutIDs.delete(timeLapseMS + callback);
}
};
}
class _IdleTimeScheduler extends _Scheduler {
events = [
'load',
'mousedown',
'mousemove',
'keydown',
'keyup',
'input',
'scroll',
'touchstart',
'touchend',
'touchcancel',
'touchmove',
];
callbacks;
constructor() {
super();
this.events.forEach(name => {
document.addEventListener(name, this.resetTimer, true);
});
this.callbacks = new Map();
}
addIdleTimeCallback = (callback, timeLapseMS) => {
this.addCallback(callback, timeLapseMS, false);
let callbacksArr = this.callbacks.get(timeLapseMS);
if (!callbacksArr) {
this.callbacks.set(timeLapseMS, [callback]);
} else {
if (!callbacksArr.includes(callback)) {
callbacksArr.push(callback);
}
}
};
removeIdleTimeCallback = (callback, timeLapseMS) => {
this.removeCallback(callback, timeLapseMS);
let callbacksArr = this.callbacks.get(timeLapseMS);
if (callbacksArr) {
let index = callbacksArr.indexOf(callback);
if (index !== -1) {
callbacksArr.splice(index, 1);
}
}
};
resetTimer = () => {
for (let [timeLapseMS, callbacksArr] of this.callbacks) {
callbacksArr.forEach(callback => {
// Clear the previous IDs
let timeoutID = this.timeoutIDs.get(timeLapseMS + callback);
clearTimeout(timeoutID);
// Create new timeout IDs.
timeoutID = setTimeout(callback, timeLapseMS);
this.timeoutIDs.set(timeLapseMS + callback, timeoutID);
});
}
};
}
export const Scheduler = new _Scheduler();
export const IdleTimeScheduler = new _IdleTimeScheduler();
其他回答
(部分灵感来自Equiman回答的良好核心逻辑。)
sessionExpiration.js
sessionExpiration.js是轻量级的，但有效和可定制的。一旦实现，只在一行中使用:
sessionExpiration(idleMinutes, warningMinutes, logoutUrl);
Affects all tabs of the browser, not just one. Written in pure JavaScript, with no dependencies. Fully client side. (If so wanted.) Has warning banner and countdown clock, that is cancelled by user interaction. Simply include the sessionExpiration.js, and call the function, with arguments [1] number of idle minutes (across all tabs) until user is logged out, [2] number of idle minutes until warning and countdown is displayed, and [3] logout url. Put the CSS in your stylesheet. Customize it if you like. (Or skip and delete banner if you don't want it.) If you do want the warning banner however, then you must put an empty div with ID sessExpirDiv on your page (a suggestion is putting it in the footer). Now the user will be logged out automatically if all tabs have been inactive for the given duration. Optional: You may provide a fourth argument (URL serverRefresh) to the function, so that a server side session timer is also refreshed when you interact with the page.
这是一个例子，如果你不改变CSS，它看起来是什么样子的。
改进Equiman(原始)的答案:
function idleLogout() {
var t;
window.onload = resetTimer;
window.onmousemove = resetTimer;
window.onmousedown = resetTimer; // catches touchscreen presses as well
window.ontouchstart = resetTimer; // catches touchscreen swipes as well
window.ontouchmove = resetTimer; // required by some devices
window.onclick = resetTimer; // catches touchpad clicks as well
window.onkeydown = resetTimer;
window.addEventListener('scroll', resetTimer, true); // improved; see comments
function yourFunction() {
// your function for too long inactivity goes here
// e.g. window.location.href = 'logout.php';
}
function resetTimer() {
clearTimeout(t);
t = setTimeout(yourFunction, 10000); // time is in milliseconds
}
}
idleLogout();
除了活动检测方面的改进，以及从文档到窗口的更改之外，这个脚本实际上调用了函数，而不是让它闲置着。
它不会直接捕获零CPU使用情况，但这是不可能的，因为执行函数会导致CPU使用。用户不活动最终导致CPU使用率为零，因此它间接地捕捉到CPU使用率为零。
就像它可以得到的那样简单，检测鼠标移动的时间:
var idle = false;
document.querySelector('body').addEventListener('mousemove', function(e) {
if(idle!=false)
idle = false;
});
var idleI = setInterval(function()
{
if(idle == 'inactive')
{
return;
}
if(idle == true)
{
idleFunction();
idle = 'inactive';
return;
}
idle = true;
}, 30000); // half the expected time. Idle will trigger after 60 s in this case.
function idleFuntion()
{
console.log('user is idle');
}
根据equiman提供的输入:
class _Scheduler {
timeoutIDs;
constructor() {
this.timeoutIDs = new Map();
}
addCallback = (callback, timeLapseMS, autoRemove) => {
if (!this.timeoutIDs.has(timeLapseMS + callback)) {
let timeoutID = setTimeout(callback, timeLapseMS);
this.timeoutIDs.set(timeLapseMS + callback, timeoutID);
}
if (autoRemove !== false) {
setTimeout(
this.removeIdleTimeCallback, // Remove
10000 + timeLapseMS, // 10 secs after
callback, // the callback
timeLapseMS, // is invoked.
);
}
};
removeCallback = (callback, timeLapseMS) => {
let timeoutID = this.timeoutIDs.get(timeLapseMS + callback);
if (timeoutID) {
clearTimeout(timeoutID);
this.timeoutIDs.delete(timeLapseMS + callback);
}
};
}
class _IdleTimeScheduler extends _Scheduler {
events = [
'load',
'mousedown',
'mousemove',
'keydown',
'keyup',
'input',
'scroll',
'touchstart',
'touchend',
'touchcancel',
'touchmove',
];
callbacks;
constructor() {
super();
this.events.forEach(name => {
document.addEventListener(name, this.resetTimer, true);
});
this.callbacks = new Map();
}
addIdleTimeCallback = (callback, timeLapseMS) => {
this.addCallback(callback, timeLapseMS, false);
let callbacksArr = this.callbacks.get(timeLapseMS);
if (!callbacksArr) {
this.callbacks.set(timeLapseMS, [callback]);
} else {
if (!callbacksArr.includes(callback)) {
callbacksArr.push(callback);
}
}
};
removeIdleTimeCallback = (callback, timeLapseMS) => {
this.removeCallback(callback, timeLapseMS);
let callbacksArr = this.callbacks.get(timeLapseMS);
if (callbacksArr) {
let index = callbacksArr.indexOf(callback);
if (index !== -1) {
callbacksArr.splice(index, 1);
}
}
};
resetTimer = () => {
for (let [timeLapseMS, callbacksArr] of this.callbacks) {
callbacksArr.forEach(callback => {
// Clear the previous IDs
let timeoutID = this.timeoutIDs.get(timeLapseMS + callback);
clearTimeout(timeoutID);
// Create new timeout IDs.
timeoutID = setTimeout(callback, timeLapseMS);
this.timeoutIDs.set(timeLapseMS + callback, timeoutID);
});
}
};
}
export const Scheduler = new _Scheduler();
export const IdleTimeScheduler = new _IdleTimeScheduler();
您可以在文档主体上附加一个单击或鼠标移动事件，以重置计时器。
有一个函数，你在定时间隔调用，检查定时器是否超过指定的时间(如1000毫秒)，并开始你的预加载。
