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JavaScript AJAX Basics (retiring) Programming AJAX Create a callback

Robbie Thomas
Robbie Thomas
31,093 Points

Create a callback

It asks to create a onreadystatechange, I did that and I'm not getting through.

app.js
var xhr = new XMLHttpRequest();
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>
Robbie Thomas
Robbie Thomas
31,093 Points

Nvm, got it. I see what I did wrong.

xhr.onreadystatechange=function(){}

1 Answer

Steven Parker
Steven Parker
221,297 Points

:point_right: It looks like you have two issues:

  • you have a semicolon in the middle of the function definition. It needs to go at the end of the line.
  • you forgot to prefix onreadystatechange with "xhr."