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

Ogechi Ike
Ogechi Ike
6,539 Points

I can't get my ajax example to work.

I have checked the video and the mdn documentation of ajax, but the ajax event won't work. It keeps saying:

Uncaught TypeError: undefined is not a function(index):12 ajax.onreadystatechangeXMLHttpRequest.send (async)(index):16 (anonymous function)

Here is my code:

      var ajax = new XMLHttpRequest();//sets up a new AJAX object
      ajax.onreadystatechange = function(){
        if(ajax.readyState === 4){
            document.getElementByID('ajax').innerHTML = ajax.responseText;
    ajax.open('GET', 'sidebar.html');//GET is the HTTP Method that gets the information from the sidebar.html
    ajax.send();//send the information from sidebar.html back to the index

1 Answer

Erik Krieg
Erik Krieg
43,038 Points

Quickly looking through I noticed that you have capitalized the "d" in the method "getElementById"

That might fix your problem, but if not, lemme know! ♥

Ogechi Ike
Ogechi Ike
6,539 Points

Thanks, Erik. I ha already found my mistake. It was the capital 'D'.