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JavaScript

Posted by Tiffany White
Tiffany White
5,373 Points

Lost, still, as to what a callback function is.

I have been researching callback functions in JavaScript for some time and I still don't know how to recognize one in code. I am also not quite sure what they do.

Can anyone help?

1 Answer

Ford Heacock
Ford Heacock
18,068 Points

Hey Tiffany! What helped me understand callback functions was learning that they are just functions being passed to other functions as a parameter. A very common one would be event listeners. Say for example you want to listen for a click event on a div:

myDiv.addEventListener('click',function(){
    alert('you clicked me!');
});

Notice the anonymous function being passed in after 'click'? This is a callback function as it is a function being passed as a parameter to yet another function (addeventlistener).

Here's a great article to read that helped me a lot: http://javascriptissexy.com/understand-javascript-callback-functions-and-use-them/