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JavaScript AJAX Basics (retiring) AJAX Concepts A Simple AJAX Example

Posted by Ignacio Uriz
Ignacio Uriz
5,042 Points

Not Working

Uncaught TypeError: Cannot set property 'innerHTML' of null(…)

<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <link href='//fonts.googleapis.com/css?family=Varela+Round' rel='stylesheet' type='text/css'> <link rel="stylesheet" href="css/main.css"> <script> var xhr = new XMLHttpRequest(); xhr.onreadystatechange = function () { if (xhr.readyState === 4) { document.getElementById('ajax').innerHTML = xhr.responseText; } }; xhr.open('GET', 'sidebar.html'); xhr.send();

</script>

</head> <body> <div class="grid-container centered"> <div class="grid-100"> <div class="contained"> <div class="grid-100"> <div class="heading"> <h1>Bring on the AJAX</h1> </div> <div id="ajax">

      </div>
    </div>
  </div>
</div>

</div> </body> </html>

Micah Murray
Micah Murray
6,913 Points
Micah Murray
Micah Murray
6,913 Points

Hi Ignacio, I tried your code and it works for me. What is the content of sidebar.html?

Micah Murray
Micah Murray
6,913 Points
Micah Murray
Micah Murray
6,913 Points

Hi Ignacio,

Everything still works when I used your content for sidebar.html. I had originally thought that something in the content of sidebar.html that was causing the error but theres not.

2 Answers

Ignacio Uriz
Ignacio Uriz
5,042 Points

Hi Micah Murray this is the content of the sidebar.html

<section> <h2>Welcome to the wonderful world of AJAX</h2> <p>This content provided to you dynamically by the XMLHTTP Request Object</p> </section>

Ignacio Uriz
Ignacio Uriz
5,042 Points
Ignacio Uriz
Ignacio Uriz
5,042 Points

That's weird,it might be an error from workspaces