How Do I Retrieve Data from an XMLHttpRequest Response?

How to Retrieve XMLHttpRequest Response Data

XMLHttpRequest provides a way to load and manipulate data from remote URLs through JavaScript. With it, you can obtain the HTML content of a website and store it in a variable for further processing.

To achieve this, execute the following steps:

1. Create an XMLHttpRequest object:

   var xhr = new XMLHttpRequest();

2. Define an event listener for the onreadystatechange event, which is triggered when the request's state changes.

   xhr.onreadystatechange = function() { ... };

3. Within the event listener, check if the request has completed (XMLHttpRequest.DONE) and retrieve the response text using xhr.responseText.

   if (xhr.readyState == XMLHttpRequest.DONE) {
       alert(xhr.responseText);
   }

4. Send an HTTP GET request to the desired URL:

   xhr.open('GET', 'http://foo.com/bar.php', true);
   xhr.send(null);

Note that cross-browser compatibility can be enhanced by using a library like jQuery, which simplifies the process and accounts for browser-specific issues:

$.get('http://example.com', function(responseText) {
    alert(responseText);
});

Keep in mind the Same Origin Policy for JavaScript, which restricts cross-origin requests. Consider using a proxy script to overcome this limitation.

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