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

Fenia Vasileiou
Fenia Vasileiou
7,349 Points
Posted by Fenia Vasileiou
Fenia Vasileiou
7,349 Points

Problem with ajax code, can not get data from my local web server's html file "sidebar.html"

I go throught the video instructions and set up a local web server "XAMPP". On file C:\xampp\htdocs resides the "sidebar.html". Loading the index.html i get the above error:

"XMLHttpRequest cannot load http://localhost:8080/sidebar.html. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'null' is therefore not allowed access."

<script>
    var xhr = new XMLHttpRequest(); 
    xhr.onreadystatechange = function () {
    if(xhr.readyState===4){
      document.getElementById('ajax').innerHTML = xhr.responseText;
    }
  };
xhr.open('GET', url='http://localhost:8080/sidebar.html');
 xhr.send();
</script>

I am a beginner with Ajax and this is my first try, any help?

3 Answers

Mustafa Başaran
Mustafa Başaran
28,046 Points
Mustafa Başaran
Mustafa Başaran
28,046 Points

Hello Fenia, Your code is fine except the following line:

xhr.open('GET', url='http://localhost:8080/sidebar.html');

So changing that to

xhr.open('GET', 'sidebar.html');

should work.

Please note that url= is redundant. Moreover, you are making an AJAX request to a page on the same folder as index.html and server...
I hope that this helps. Best regards, Mustafa

thomascawthorn
thomascawthorn
22,986 Points
thomascawthorn
thomascawthorn
22,986 Points

How are you getting on with this?

Fenia Vasileiou
Fenia Vasileiou
7,349 Points
Fenia Vasileiou
Fenia Vasileiou
7,349 Points

Thank you for your answer, it worked!!