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JavaScript AJAX Basics Programming AJAX Create a callback

Posted by William Ray Noble
William Ray Noble
22,190 Points

Isn't this the event handler?

I thought this was how one completes this code. I'm not sure what I'm missing. Thanks in advance!

Ray

app.js 
var xhr = new XMLHttpRequest();
xhr.onreadystatechange();
xhr.open('GET', 'sidebar.html');
xhr.send();
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>AJAX with JavaScript</title>
  <script src="app.js"></script>
</head>
<body>
  <div id="main">
    <h1>AJAX!</h1>
  </div>
  <div id="sidebar"></div>
</body>
</html>

1 Answer

Steven Parker
Steven Parker
229,788 Points
Steven Parker
Steven Parker
229,788 Points

The task is not to call the method yourself, but to assign a function to it. For this particular exercise, the function assigned doesn't need to do anything:

xhr.onreadystatechange = function() { };