Is there a way to delay function calls or statements by a given amount in milliseconds?

Question

I am creating a Chrome extension that, while on a Udemy course page, checks all the videos, so the certificate will become available, but I am encountering a problem where I activate the click event on all the needed buttons, but this happens so fast that my console gets spammed with net::ERR_INSUFFICIENT_RESOURCES, and only half of all the buttons get clicked and send the POST request to the Udemy servers. Now I was looking for a sleep() function, and a google search told me there isn't one in javascript.

This is the code I am using.

function clickButtons() {
    var buttons = document.getElementsByClassName("curriculum-item--progress--3eKMJ btn btn-default")
    for (i = 0; i < buttons.length; i++) {
    clickButton(buttons, i)

}

}
function clickButton(buttonsArray, index){ 
    buttonsArray[index].click();
}

clickButtons();

If theres another way to circumvent this issue, that would also be appreciated.

You can use the simple method setTimeout to delay your function by an amount in milliseconds, check https://www.w3schools.com/jsref/met_win_settimeout.asp — Mathieu Dfr, Feb 07 '19 at 01:38
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Nick Parsons · Answer 1 · 2019-02-13T03:36:55.353

You could create a delay method using aync and await:

const delay = t => new Promise(res => setTimeout(res, t));

(async _ => { // declare as async (as we need to use await)
  console.log("Hello");
  await delay(2000); // 2000 m/s (2 second) delay
  console.log("World!");
})();

However, with that being said, I think it is best to maybe work out a callback of some sort which triggers another button click, which triggers the next etc...

score 0 · Answer 2 · answered Feb 07 '19 at 01:41

There is a workaround/alternative. In your clickButtons() function you can wrap the call to clickButton with a setTimeout(). Like this:

setTimeout(function(){
    clickButton(buttons, i)
}, 2000);

Which would delay each call in your loop by your set timeout.

Also referenced here JavaScript sleep/wait before continuing

Is there a way to delay function calls or statements by a given amount in milliseconds?

2 Answers2