Post Data with the JavaScript XMLHttpRequest Method url not found

Post Data with the JavaScript XMLHttpRequest Method url not found


Tell us what’s happening:

where to post the requet . I can’t find the varibale of url. any helps are appreciated.

Your code so far

      var userName=document.getElementById('name').value;
      // Add your code below this line
      var req = new XMLHttpRequest();"POST","/json/cats.json",true);
      req.onreadystatechange = function(){
          document.getElementsByClassName("message")[0].innerHTML = req.responseText;
      // Add your code above this line
  body {
    text-align: center;
    font-family: "Helvetica", sans-serif;
  h1 {
    font-size: 2em;
    font-weight: bold;
  .box {
    border-radius: 5px;
    background-color: #eee;
    padding: 20px 5px;
  button {
    color: white;
    background-color: #4791d0;
    border-radius: 5px;
    border: 1px solid #4791d0;
    padding: 5px 10px 8px 10px;
  button:hover {
    background-color: #0F5897;
    border: 1px solid #0F5897;
<h1>Cat Friends</h1> 
<p class="message box">
  Reply from Server will be here
  <label for="name">Your name:
    <input type="text" id="name"/>
  <button id="sendMessage">
    Send Message

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36.

Link to the challenge:


I think the URL is stored in a variable called “url”, like in the example, try that.


I can’t understand what is the solution. I know the url should be the variable with the value of the URL. But I can’t see where it is assigned or for that matter what value to assign to it.


I think it is defined by the testing framework, behind the scenes. Don’t worry about it.