JSON Request using Javascript

Hi,

I am having problems with trying to make a call another website which returns a json response using a JavaScript. I have been trying different techniques but all of them failed.

This is the code that I have

<script type="text/javascript">
function loadJSON(url) {
var headID = document.getElementsByTagName("head")[0];
var newScript = document.createElement('script');
newScript.type = 'text/javascript';
newScript.src = url;
headID.appendChild(newScript);
}

function processJSON(feed)
{
var jsonResponse = new Function("return " + feed)();
document.writeln(jsonResponse);
alert(jsonResponse.title);
}

I am not able to tell you the website since its confidential. Basically I am requesting by passing the web url such as this:

<script type="text/javascript">
loadJSON('http://www.somewebsite.com/code/load?id=654987');
</script>

if i type the url 'http://www.somewebsite.com/code/load?id=654987', it will return a JSON response of the form

{"text":"textValue", "title":"titleValue"}

I am trying to show the text and title in a <div> tag within the body. How can I make the request using Javascript?

 

As far as I know, you can add on your site the content obtained from other sites (like IFRAME do). For example: Google Adsense Ads works that way. But you can NOT read that content, because cross domain scripting is not available on browsers for security reasons.

 

I have tried using different techniques such as XMLHTTP, dojo.IFrame, and now I am trying to use RCP. Is there another technique that I missed?

This whole project is for a sidebar Firefox extension which lets user login into the website and send a request to the www.something.com and get the json response and display it on the sidebar.

Is this hard to do? Any examples that you can link me to?