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JavaScript AJAX Basics (retiring) jQuery and AJAX Add a callback

Melanie Loff-Bird
Melanie Loff-Bird
941 Points
Posted by Melanie Loff-Bird
Melanie Loff-Bird
941 Points

How do you add a callback function?

Keep getting an error, don't know what the callback function should be.

app.js 
$.get("footer.html");
function(response) {
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>AJAX with JavaScript</title>
</head>
<body>
  <div id="main">
    <h1>AJAX with jQuery</h1>
  </div>
  <div id="footer"></div>
  <script src="jquery.js"></script>
  <script src="app.js"></script>
</body>
</html>

2 Answers

Jason Arnold
Jason Arnold
22,110 Points

In the case of an AJAX request, the callback function is what you want to script to do with the data that is returned. In your case, it looks like you want to pass an htmlString of data from the 'footer.html' file into, I'm guessing, your 'footer' div? So the inside of your function might look something like this

$.get("footer.html", function(response) {
    $('#footer').html(response);
});
Rafael Capati
Rafael Capati
10,725 Points
Rafael Capati
Rafael Capati
10,725 Points

Hi Melanie.

Functions occasionally take function pointers as arguments, which are generally used as callbacks, passing an anonymous function as the second argument to the .get tmethod:

$.get("footer.html", function(res) {

});