Subj : Re: client-side Javascript HTTP
To   : netscape.public.mozilla.jseng,netscape.public.mozilla.dom
From : Martin Honnen
Date : Sun Oct 31 2004 12:24 pm



Felipe Gasper wrote:


>     Does anyone out there know if there's a way for client-side 
> Javascript to fetch a text file via HTTP and read its contents into a 
> variable? The best I can do so far is creating an IFRAME element (via 
> DOM), which does display the text I want, but from there I can't find a 
> way to read the frame's contents into a veriable.

Wrong newsgroup, see netscape.public.mozilla.dom for followup.

As for the problem, some browsers by now implement an object with an API 
mainly meant to exchange XML data with the server via HTTP but you can 
also use that API to read text (as long as it is UTF-8 encoded that is).
   function getTextContent (url, contentHandler) {
     var httpRequest;
     if (typeof XMLHttpRequest != 'undefined') {
       httpRequest = new XMLHttpRequest();
     }
     else if (typeof ActiveXObject != 'undefined') {
       try {
         httpRequest = new ActiveXObject('Microsoft.XMLHTTP');
       }
       catch (e) {
         httpRequest = null;
       }
     }
     if (httpRequest) {
       httpRequest.open('GET', url, true);
       httpRequest.onreadystatechange = function (evt) {
         if (httpRequest.readyState == 4) {
           contentHandler(httpRequest.responseText);
         }
       };
       httpRequest.send(null);
     }
   }

   getTextContent(location.href, function (text) { alert(text); })

That code should work with IE 5 and later on Windows, Netscape 7, 
Mozilla, Firefox. Safari 1.2 and Opera 7.60 (currently only available as 
a preview) also make attempts to implement XMLHttpRequest but so far do 
not provide the full API and versatility, the above fails to display 
anything for me here with Opera 7.60 Preview 2. I don't have Safari to 
test here.

For more details see
   http://www.faqts.com/knowledge_base/view.phtml/aid/17226/fid/616
and
   http://jibbering.com/2002/4/httprequest.html

-- 

	Martin Honnen
	http://JavaScript.FAQTs.com/

.