How to use setInterval or setTimeout with a for loop?

Question

I am trying to set an interval when some code runs but only need to do it based on the number of elements there are. Here\'s a quick example:

5 total elements

Ru

Answer 1

You have to define a function, and inside the function it needs to set a timeout on itself. Like this:

var els = [1, 2, 3, 4, 5];

((function process_els(el_index) {
  var el = els[el_index];

  // do stuff to el here
  console.log(el);
  // do stuff to el above

  if (el_index + 1 < els.length) {
    setTimeout(function() { process_els(el_index + 1); }, 20000);
  }
})(0);