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

Christos Tsamis
Christos Tsamis
8,091 Points
Posted by Christos Tsamis
Christos Tsamis
8,091 Points

has been blocked by CORS policy

Code is right, debuged it and and faced a CORS policy problem.. Any ideas?

Juan Lopez
.a{fill-rule:evenodd;}techdegree seal-36
Juan Lopez
Treehouse Project Reviewer

Any chance on you posting your code?

Juan Lopez
.a{fill-rule:evenodd;}techdegree seal-36
Juan Lopez
Treehouse Project Reviewer

3 backticks

    ```javascript 
    /* Your code here*/
    ```
Christos Tsamis
Christos Tsamis
8,091 Points
Christos Tsamis
Christos Tsamis
8,091 Points 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <link href='http://fonts.googleapis.com/css?family=Varela+Round' rel='stylesheet' type='text/css'>
  <link rel="stylesheet" href="main.css">
  <title>AJAX with JavaScript</title>
  <script>
  var xhr = new XMLHttpRequest();
  xhr.open('GET', 'sidebar.html');
  xhr.onreadystatechange = function () {
    if (xhr.readyState === 4) {
      document.getElementById('ajax').innerHTML = xhr.responseText;
    }
  };

  function sendAJAX() {
    xhr.send();
    document.getElementById('load').style.display = 'none';
  }
  </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>
          <button id="load" onclick="sendAJAX()" class="button">Bring it!</button>
          <ul id="ajax">

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

(thanks by the way ^^ )

2 Answers

Christos Tsamis
Christos Tsamis
8,091 Points
Christos Tsamis
Christos Tsamis
8,091 Points

i am doing so, i will try that! thanks!

Kevin Lewis
Kevin Lewis
15,088 Points

Worked for me. Thank you!

Eric Butler
Eric Butler
33,512 Points
Eric Butler
Eric Butler
33,512 Points

This is actually a really common frustration for developers and likely has nothing to do with your code: As a security feature, Chrome does not allow "cross-origin resource sharing" when you're working on localhost or just using File>Open to load a webpage locally. There are a few work-arounds, the best of which might be to run a local server with a domain alias -- but I understand that's asking a lot if you've never done it and just want to do this one thing. I personally would not suggest setting any flags --disable-web-security that would compromise your browser. Here's some discussion about it: https://stackoverflow.com/questions/10883211/deadly-cors-when-http-localhost-is-the-origin.

Christos Tsamis
Christos Tsamis
8,091 Points
Christos Tsamis
Christos Tsamis
8,091 Points

Eric Butler thank you, i run the project on a local server.... had to change browser to follow up the course.. thank you for your answer!