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JavaScript AJAX Basics (retiring) Programming AJAX Create a callback

Posted by Santhosh Bandila
Santhosh Bandila
4,465 Points

On line 2 of the app.js file, add an onreadystatechange event handler. Add an anonymous function, but don't put any code

On line 2 of the app.js file, add an onreadystatechange event handler. Add an anonymous function, but don't put any code

app.js 
var xhr = new XMLHttpRequest();
xmlhttp.onreadystatechange=function(){}
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

Grace Kelly
Grace Kelly
33,990 Points
Grace Kelly
Grace Kelly
33,990 Points

You're almost there, you just need to add the onreadystatechange event handler to the xhr variable, like so:

xhr.onreadystatechange=function(){} //use xhr variable

Hope that helps!!