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JavaScript AJAX Basics (retiring) Programming AJAX Check for the correct ready state

Posted by Susan Stufflebean
Susan Stufflebean
7,466 Points

Why is this not passing?

As you see I have added the correct code (I believe?) but when I check work it states my Task 1 is no longer passing? Why?

app.js 
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if (xhr.readyState === 4 && xhr.status === 200){ xhr.status;
   document.getElementById('sidebar');.innerHTML = xhr.responseText;                                           
  };
};
xhr.open('GET', 'sidebar.html');
xhr.send();
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>AJAX with JavaScript</title>
  <script src="app.js"></script>
</head>
<body>
  <div id="main">
    <h1>AJAX!</h1>
  </div>
  <div id="sidebar"></div>
</body>
</html>

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Any syntax error invalidates the entire script and causes the re-validations to fail.

In this case, the error is the stray semicolon in this expression: "document.getElementById('sidebar');.innerHTML".

Also, while they don't cause errors, there are two more oddities in this code:

  • the statement "xhr.status;" doesn't do anything
  • there's a superfluous semicolon after the "if" code block