Ajax problem with IE?

[txbakers]

I have a strange problem coming up. I have a simple Ajax screen where the user checks a checkbox and it updates the database. then, after the database is updated, it queries and is supposed to display an appropriate message.

On my test machines (IE7) it works perfectly every time.

On my clients Safari (MAC) it works perfectly.

On her IE7 and IE6 on various machines, it is not working correctly - she has cleared cache, forced refresh, and still the browser hangs on to the old.

What would cause IE to hang on to the old data and not run the Ajax?

she has also adjusted the Cache to pull a new page every time.

I'm stumped and so is she.

Thanks.

[DrDoc]

It depends on which MSXML version is used. Make sure you do something similar to this (in the same order as indicated):

var xmlHttp; 
try { 
  // Firefox, Opera 8.0+, Safari 
  xmlHttp=new XMLHttpRequest(); 
} 
catch (e) { 
  // Internet Explorer 
  try { 
    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); 
  } 
  catch (e) { 
    try { 
      xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); 
    } 
    catch (e) { 
      alert("Your browser does not support AJAX!"); 
      return false; 
    } 
  } 
}

[txbakers]

Thanks Doc, that's what I have, except my first line sets xmlHttp = null;

should that matter?

Thanks.

[DrDoc]

Nope, that shouldn't matter.

Are the security settings different on your client's machine? Anything else different between the two?

[penders]

Have had problems with IE's caching behaviour in the past... having to resort to appending timestamps on the XMLHttpRequest to get around the issue.

[txbakers]

timestamps sounds cool. How does that work, can you post a code sample?

[DrDoc]

var uri = "http://www.example.com/foo/";
var now = new Date();
var uts = now.getTime();
uri = uri + "?" + uts;

[txbakers]

ok so just add that as a parameter, easy enough. But does it help with the Ajax running in the background?

[DrDoc]

If each request adds the Unix timestamp as a parameter, yes. That should address the caching problem (assuming that's what's causing you trouble).