How do I write a callback to an immediately invoked function in a loop?

Question

I have a loop to gather all elements of a certain class and insert something into that element.

var node;
var nodes = document.getElementsByClassName('myclass');
for(var i = 1; i <= nodes.length; ++i) {
  function () {
    var element = document.creatElement('script');
    node = document.getElementById('my-node' + i);
    node.parentNode.insertBefore(element, node);
  })();
}

I have some code that I need to make a callback to this because it uses the id of node but when I run that code it only runs on the last element of the array even if I call it in the for loop. Basically what I need is to keep the value of the node variable and use it in a callback function each pass through the loop.

If I understand javascript correctly, this means I need a callback, but I dont know how to write one for an immediately invoked function.

http://stackoverflow.com/questions/750486/javascript-closure-inside-loops-simple-practical-example — Teemu, Mar 18 '16 at 21:45
Teemu, this is exactly what i needed. and a much better way to word the question! — BrandenB171, Mar 18 '16 at 21:49

score 1 · Answer 1 · answered Mar 18 '16 at 21:22

1

I did not understand exactly what you want, but if you want to keep the value you need to pass it to the function due the closure :

 var nodes = document.getElementsByClassName('myclass');
  for(i=1; i<=nodes.length; ++i){
    function(valueofI){
    var element = document.creatElement('script');
    node = document.getElementById('my-node'+valueofI);
    node.parentNode.insertBefore(element, node);
  })(i);
}

I hope it is what you need.

answered Mar 18 '16 at 21:22

Jesse Teixeira

131
1
4

i need to keep value of node actually but i think this will actually do well enough as an example – BrandenB171 Mar 18 '16 at 21:35

How do I write a callback to an immediately invoked function in a loop?

1 Answers1