问题
I am using setInterval(fname, 10000); to call a function every 10 seconds in JavaScript. Is it possible to stop calling it on some event?
I want the user to be able to stop the repeated refresh of data.
回答1:
setInterval() returns an interval ID, which you can pass to clearInterval():
var refreshIntervalId = setInterval(fname, 10000);
/* later */
clearInterval(refreshIntervalId);
See the docs for setInterval() and clearInterval().
回答2:
If you set the return value of setInterval to a variable, you can use clearInterval to stop it.
var myTimer = setInterval(...);
clearInterval(myTimer);
回答3:
You can set a new variable and have it incremented by ++ (count up one) every time it runs, then I use a conditional statement to end it:
var intervalId = null;
var varCounter = 0;
var varName = function(){
if(varCounter <= 10) {
varCounter++;
/* your code goes here */
} else {
clearInterval(intervalId);
}
};
$(document).ready(function(){
intervalId = setInterval(varName, 10000);
});
I hope that it helps and it is right.
回答4:
The answers above have already explained how setInterval returns a handle, and how this handle is used to cancel the Interval timer.
Some architectural considerations:
Please do not use "scope-less" variables. The safest way is to use the attribute of a DOM object. The easiest place would be "document". If the refresher is started by a start/stop button, you can use the button itself:
<a onclick="start(this);">Start</a>
<script>
function start(d){
if (d.interval){
clearInterval(d.interval);
d.innerHTML='Start';
} else {
d.interval=setInterval(function(){
//refresh here
},10000);
d.innerHTML='Stop';
}
}
</script>
Since the function is defined inside the button click handler, you don't have to define it again. The timer can be resumed if the button is clicked on again.
回答5:
Already answered... But if you need a featured, re-usable timer that also supports multiple tasks on different intervals, you can use my TaskTimer (for Node and browser).
// Timer with 1000ms (1 second) base interval resolution.
const timer = new TaskTimer(1000);
// Add task(s) based on tick intervals.
timer.add({
id: 'job1', // unique id of the task
tickInterval: 5, // run every 5 ticks (5 x interval = 5000 ms)
totalRuns: 10, // run 10 times only. (omit for unlimited times)
callback(task) {
// code to be executed on each run
console.log(task.name + ' task has run ' + task.currentRuns + ' times.');
// stop the timer anytime you like
if (someCondition()) timer.stop();
// or simply remove this task if you have others
if (someCondition()) timer.remove(task.id);
}
});
// Start the timer
timer.start();
In your case, when users click for disturbing the data-refresh; you can also call timer.pause() then timer.resume() if they need to re-enable.
See more here.
回答6:
@cnu,
You can stop interval, when try run code before look ur console browser (F12) ... try comment clearInterval(trigger) is look again a console, not beautifier? :P
Check example a source:
var trigger = setInterval(function() {
if (document.getElementById('sandroalvares') != null) {
document.write('<div id="sandroalvares" style="background: yellow; width:200px;">SandroAlvares</div>');
clearInterval(trigger);
console.log('Success');
} else {
console.log('Trigger!!');
}
}, 1000);
<div id="sandroalvares" style="background: gold; width:200px;">Author</div>
回答7:
The clearInterval() method can be used to clear a timer set with the setInterval() method.
setInterval always returns a ID value. This value can be passed in clearInterval() to stop the timer. Here is an example of timer starting from 30 and stops when it becomes 0.
let time = 30;
const timeValue = setInterval((interval) => {
time = this.time - 1;
if (time <= 0) {
clearInterval(timeValue);
}
}, 1000);
回答8:
Declare variable to assign value returned from setInterval(...) and pass the assigned variable to clearInterval();
e.g.
var timer, intervalInSec = 2;
timer = setInterval(func, intervalInSec*1000, 30 ); // third parameter is argument to called function 'func'
function func(param){
console.log(param);
}
// Anywhere you've access to timer declared above call clearInterval
$('.htmlelement').click( function(){ // any event you want
clearInterval(timer);// Stops or does the work
});
回答9:
var keepGoing = true;
setInterval(function () {
if (keepGoing) {
//DO YOUR STUFF HERE
console.log(i);
}
//YOU CAN CHANGE 'keepGoing' HERE
}, 500);
You can also stop the interval by adding an event listener to let's say a button with the ID "stop-interval":
$('buuton#stop-interval').click(function(){
keepGoing = false;
});
HTML:
<button id="stop-interval">Stop Interval</button>
Note: The interval will still be executed, nothing will happen though.
回答10:
This is how I used clearInterval() method to stop the timer after 10 seconds.
function startCountDown() {
var countdownNumberEl = document.getElementById('countdown-number');
var countdown = 10;
const interval = setInterval(() => {
countdown = --countdown <= 0 ? 10 : countdown;
countdownNumberEl.textContent = countdown;
if (countdown == 1) {
clearInterval(interval);
}
}, 1000)
}
<head>
<body>
<button id="countdown-number" onclick="startCountDown();">Show Time </button>
</body>
</head>
回答11:
Use setTimeOut to stop the interval after some time.
var interVal = setInterval(function(){console.log("Running") }, 1000);
setTimeout(function (argument) {
clearInterval(interVal);
},10000);
回答12:
Why not use a simpler approach? Add a class!
Simply add a class that tells the interval not to do anything. For example: on hover.
var i = 0;
this.setInterval(function() {
if(!$('#counter').hasClass('pauseInterval')) { //only run if it hasn't got this class 'pauseInterval'
console.log('Counting...');
$('#counter').html(i++); //just for explaining and showing
} else {
console.log('Stopped counting');
}
}, 500);
/* In this example, I'm adding a class on mouseover and remove it again on mouseleave. You can of course do pretty much whatever you like */
$('#counter').hover(function() { //mouse enter
$(this).addClass('pauseInterval');
},function() { //mouse leave
$(this).removeClass('pauseInterval');
}
);
/* Other example */
$('#pauseInterval').click(function() {
$('#counter').toggleClass('pauseInterval');
});
body {
background-color: #eee;
font-family: Calibri, Arial, sans-serif;
}
#counter {
width: 50%;
background: #ddd;
border: 2px solid #009afd;
border-radius: 5px;
padding: 5px;
text-align: center;
transition: .3s;
margin: 0 auto;
}
#counter.pauseInterval {
border-color: red;
}
<!-- you'll need jQuery for this. If you really want a vanilla version, ask -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p id="counter"> </p>
<button id="pauseInterval">Pause</button></p>
I've been looking for this fast and easy approach for ages, so I'm posting several versions to introduce as many people to it as possible.
来源:https://stackoverflow.com/questions/109086/stop-setinterval-call-in-javascript