Develop Reference

Set interval works only first time. Is there any solution?

I want to run the function continuously. But it only works first time properly. Is there any solution for working this function continuously?
$(document).ready(function() {
setInterval(() => {
$('#open-band').trigger('click');
setTimeout(() => {
$('#close-band').trigger('click');
}, 50000);
}, 15000);
});

If the code inside the setInterval takes longer than the time you have set it will create another process before the function finishes messing everything up. So choosing setTimeout is actually better.
To make a function loops in setTimeout use a following syntax:
function function1() {
// something here
}
function runner() {
function1();
setTimeout(function() {
runner();
}, time);
}
runner();

Given the comment under the question explaining your goal:
I want to trigger a button to show a div after 15 secs when the page is loaded, and 50 secs later another trigger for closing the div. & I want to run this continuously
I would suggest that you chain setTimeout() calls instead of using setInterval() which will cause the events to overlap and become a mess. I'd also suggest that you call show() and hide() directly on the required elements instead of faking click events in the DOM. Try this:
function openBand() {
$('#yourElement').show();
setTimeout(closeBand, 50000);
}
function closeBand() {
$('#yourElement').hide();
setTimeout(openBand, 15000);
}
$(document).ready(function() {
setTimeout(openBand, 15000);
// or just call closeBand() here directly, if the element starts as hidden
});

You should change your current function with this one
$(document).ready(function() {
setInterval(() => {
$('#open-band').trigger('click');
}, 15000);
setTimeout(() => {
$('#close-band').trigger('click');
}, 50000);
});

JS setTimeout stack

why does setTimeout not work? And how to do this action properly? I need to get 30s delay every submit. Sorry for newbie question, but i am newbie.
if (event.target.id.indexOf('submit') === 0)
{ post1000.submit(); setTimeout('post1001.submit();', 30000); }
{ post1001.submit(); setTimeout('post1002.submit();', 60000); }
...
{ post5092.submit(); setTimeout('post5093.submit();', 122790000); }
}, false);

You can also try something like this;
setTimeout(yourSubmitFunction, 3000)
function yourSubmitFunction() {
//do whatever you want to do you can define submit here
}
You can call setTimeout in a loop, like for each element in your array which has your "post****" variables.

I believe you shouln't use a string as first parameter for setTimeout();
Here is this function definition :
setTimeout(function,milliseconds,param1,param2,...)
Try with this code sample, or update yours accordingly :
setTimeout(function(){ alert("Hello"); }, 3000);

Using Javascript for button and timed alert

I'm trying to create a button with a timer to an alert. User clicks button, two seconds later an alert pops up.
My code is resulting in the alert appearing on page load, and then again two seconds later, regardless of button click.
var timer = setTimeout('timeUp()', 2000)
function timeUp() {
alert("Time's Up!");
}
document.getElementById("startGame").addEventListener('click', timeUp());

function timeUp() {
setTimeout(function(){
alert("Time's Up!");
}, 2000);
}
document.getElementById("startGame").addEventListener('click', timeUp);

It should be:
function timeUp() {
var timer = setTimeout('alert("Time\'s Up!")', 2000);
}
document.getElementById("startGame").addEventListener('click', timeUp);

[UPDATED]
I made you an example code pen :).
Simply a case of re factoring your original code a little. Take a look:
function timeUp() {
setTimeout(function(){
return alert("hi");
}, 2000);
}
document
.getElementById("startGame")
.addEventListener('click', timeUp);
Here is the link to the full codepen example.
Codepen example

Function not repeating in Javascript?

I have a function in Javascript that I need to repeat every 5 seconds.
Here is the simple code:
function myFunk() {
$('body').addClass('polyonloaded');
setTimeout(myFunk, 5000);
}
myFunk();
It runs the function once, and does not repeat it anymore. What went wrong with my code?

Your code is working; try printing something:
function myFunk() {
$('body').addClass('polyonloaded');
console.log('hello');
setTimeout(myFunk, 5000);
}
myFunk();
The problem: since the added class is always the same, nothing happens:
the class is already added; it won't be added again.
If you want to add, remove, add, remove, ... etc. use toggleClass:
function myFunk() {
$('body').toggleClass('polyonloaded');
setTimeout(myFunk, $('body').hasClass('polyonloaded') ? 4000 : 5000);
}
myFunk();

You have to add and remove the class.
Set an interval that adds the class, then set a timeout inside to wait a bit that removes it, just before the next interval.
Forked yours here:
http://codepen.io/snlacks/pen/KwoELp
$(document).ready(function() {
setInterval( function() {
$('body').addClass('polyonloaded');
setTimeout( function(){
$('body').removeClass('polyonloaded');
}, 4000)}, 5000 );
});

Seems to be working fine:
function myFunk() {
console.log('running');
setTimeout(myFunk, 1000);
}
myFunk();
http://jsfiddle.net/dem6u89L/

Getting jquery to delay after adding a class

I want a script to halt before continuing after adding a class, below are two attempts that seem to fail.
window.setTimeout($("#"+item).addClass("highlight"), 5000 );
$("#"+item).addClass("highlight").delay(5000);
Where am I going wrong here?

Another way:
$("#"+item).addClass("highlight");
setTimeout(function(){
//rest of the code
}, 5000);

You want something like:
function addClassAndDelay(item, nextMenu) {
$("#"+item).addClass("highlight");
window.setTimeout(function() { restOfCode(nextMenu); }, 5000);
}
function restOfCode(nextMenu) {
jQT.goTo('#'+nextMenu, 'slide');
}

May be you are looking for the jQuery Highlight plugin?
$("#mydiv").click(function () {
$(this).effect("highlight", {}, 3000);
});