Javascript - telling setInterval to only fire x amount of times?_问答_开发者

Is it possible to limit the amount of times that setInterval will fire i开发者_C百科n javascript?

You can call clearInterval() after x calls:

var x = 0;
var intervalID = setInterval(function () {

   // Your logic here

   if (++x === 5) {
       window.clearInterval(intervalID);
   }
}, 1000);

To avoid global variables, an improvement of the above would be:

function setIntervalX(callback, delay, repetitions) {
    var x = 0;
    var intervalID = window.setInterval(function () {

       callback();

       if (++x === repetitions) {
           window.clearInterval(intervalID);
       }
    }, delay);
}

Then you can call the new setInvervalX() function as follows:

// This will be repeated 5 times with 1 second intervals:
setIntervalX(function () {
    // Your logic here
}, 1000, 5);

I personally prefer to use setTimeout() spaced out to achieve the same effect

// Set a function to run every "interval" seconds a total of "x" times
var x = 10;
var interval = 1000;

for (var i = 0; i < x; i++) {
    setTimeout(function () {
        // Do Something
    }, i * interval)
}

There's no clean up required with clearInterval()

You can enclose it to avoid variables leaking and it looks pretty clean :)

// Definition
function setIntervalLimited(callback, interval, x) {

    for (var i = 0; i < x; i++) {
        setTimeout(callback, i * interval);
    }

}

// Usage
setIntervalLimited(function() {
    console.log('hit');          // => hit...hit...etc (every second, stops after 10)
}, 1000, 10)

You can set a timeout that calls clearInterval. This should work:

function setTimedInterval(callback, delay, timeout){
    var id=window.setInterval(callback, delay);
    window.setTimeout(function(){
        window.clearInterval(id);
    }, timeout);
}

You can use setTimeout and a for loop.

var numberOfTimes = 20;
delay = 1000;

for (let i = 0; i < numberOfTimes; i++) {
    setTimeout( doSomething, delay * i);
}

This will clear the interval after 10 calls

<html>
<body>

<input type="text" id="clock" />
<script language=javascript>
var numOfCalls = 0;
var int=self.setInterval("clock()",1000);
function clock()
  {
  var d=new Date();
  var t=d.toLocaleTimeString();
  document.getElementById("clock").value=t;
  numOfCalls++;
  if(numOfCalls == 10)
     window.clearInterval(int);
  }
</script>
</form>


</body>
</html>

I made a small package that does this for NodeJS.

https://www.npmjs.com/package/count-interval

It's a drop-in replacement for setInterval (including parameter passing), but it takes an additional count parameter. This example prints a message once every second, but only 3 times.

const countInterval = require('./countInterval');

const timer = countInterval(() => {
   console.log('fired!', new Date());
}, 1000, 3);

And for those of you preferring setTimeout and loving recursion here is my suggestion ;)

const setIntervalX = (fn, delay, times) => {
  if(!times) return

  setTimeout(() => {
    fn() 
    setIntervalX(fn, delay, times-1)
  }, delay)
}

Then as suggested you can call the new setInvervalX() function as follows:

// This will be repeated every for 5 times with 1 second intervals:
setIntervalX(function () {
    // Your logic here
}, 1000, 5);

You can do this actually very simply with setTimeout() and an incremental counter.

var i = 0; // counter for the timer
function doSomething() {
    console.log("1 second"); // your actual code here, alternatively call an other function here
    if (++i < 10)
    {   // only reset the timer when maximum of 10 times it is fired 
        console.log("reset the timer");
        setTimeout(doSomething, 1000); // reset the timer
    }
}
setTimeout(doSomething, 1000);  // init the first

This answer is based on SO: Repeating setTimeout and a nice, neat and tidy small combination with this.

You can use Six

SetIntervalX: Limit the number of times that setInterval will fire

import { setIntervalX } from "https://deno.land/x/six/mod.ts";
import { randomNumber } from "https://deno.land/x/random_number/mod.ts";

const API_URL = "https://leap.deno.dev";

async function checkAPIStatus() {
  const startTime = performance.now();

  const randomYear = randomNumber({ min: 2000, max: 10_000 });

  const response = await fetch(`${API_URL}/${randomYear}`);

  const data = await response.json();

  console.log(`Is ${randomYear} a leap year? ${data.leapYear}.`);

  const entTime = performance.now();

  console.log(`Request took ${(entTime - startTime) / 1000} seconds.`);
}

setIntervalX(checkAPIStatus, 2000, 15);

Web Page: https://ulti.js.org/six

Repository: https://github.com/UltiRequiem/six

It includes documentation, 100% code coverage, and examples!

Works on Deno, Node.js and the browser!