2 makeRequest run one after another not working with Explorer

[celia05es]

Hello,
I have a js function that calls a AJAX function. Then, if the return code is correct, another AJAX function is called. It works perfectly with Mozilla but I am having a problem with Explorer... the 2nd AJAX call is not performed!!!

I have put an alarm after the command: http_request.open('GET', url, true); alert("AFTER OPEN"); http_request.send(null);

WIth Mozilla the alarm is fired but not with EXPLORER.

Could you tell me what is wrong please?

It seems that if a http_request.open is done, a second one cannot be done.

Thanks a lot

Here is part of the code. I don't know a lot about AJAX so I'm sure the solution will be easy for you to find:

First the makeRequest(0,url) command is executed... then the following line is executed: http_request.onreadystatechange = alertContents;
The alertContents function then calls makeRequest(1,url)... This is when the problem happens!!
Could you help!

..
function add()
{
// Add the address
//-----------------------
target=1;
myRand=parseInt(Math.random()*99999999); // cache buster
var url="addVlr.jsp?rand="+myRand+"&vlrAddress="+new_vlr_address;
[B]makeRequest(0,url);[/B]
}
...
function makeRequest(option,url)
{
http_request = false;

if (window.XMLHttpRequest)  // Mozilla, Safari,...
{
  http_request = new XMLHttpRequest();
  if (http_request.overrideMimeType)
  {
    http_request.overrideMimeType('text/xml');
  }
}
else
{
 if (window.ActiveXObject)  // IE
 {
   try
   {
     http_request = new ActiveXObject("Msxml2.XMLHTTP");
   }
   catch (e)
   {
    try
    {
     http_request = new ActiveXObject("Microsoft.XMLHTTP");
    } 
    catch (e) {}
   }
 }
}

if (!http_request)
{
  alert('Giving up. Cannot connect.');
  return false;
}
if (option == 0)
{
  http_request.onreadystatechange = alertContents;
}
else
{
  http_request.onreadystatechange = alertContents1;
}
[B]http_request.open('GET', url, true);
alert("AFTER OPEN");
http_request.send(null);[/B]
}

function alertContents()
{
  if (http_request.readyState == 4)  // COMPLETE
  {
    if (http_request.status == 200)
    {
      var values = http_request.responseText;
      ier=trim(values);
      if (ier !=0)
      {
        alert(ier);
      }
      else
      {
        // Treatment goes here
           ....
        if (target == 1)
        {
          // Add address to array and sort it
          //---------------------------------
           myRand=parseInt(Math.random()*99999999); 
           var vlr_list=document.forms[1].vlr.value;
           var url="sortVlr.jsp?rand="+myRand+"&vlrList="+vlr_list+"&vlrAddress=
"+new_vlr_address;
           document.forms[1].vlr_addr.value="";
          [B] makeRequest(1,url);[/B]
        }
      }
    }
    else
    {
      alert("Problem");
    }
  }
}

[digital-ether]

Do you get any errors? Try wrapping your functions in

try { } catch(e) { alert(e); }

See if IE gives errors. I know IE sucks at error reporting.

[celia05es]

Well, I have tried what you suggested and the error is.... "Object error"!!!
The register is added (which means that the 1st makeRequest is performed properly) but when in the makeRequest I call another makeRequest.... the error occurs!! Is there a way of doing it differently. I mean, first I add the register. THen if no error I sort it and show it. When I want to sort it, and call AJAX, I have the "Object error" error!
Thanks for your help.

[digital-ether]

Well, I have tried what you suggested and the error is.... "Object error"!!!
The register is added (which means that the 1st makeRequest is performed properly) but when in the makeRequest I call another makeRequest.... the error occurs!! Is there a way of doing it differently. I mean, first I add the register. THen if no error I sort it and show it. When I want to sort it, and call AJAX, I have the "Object error" error!
Thanks for your help.

Is the function alertContents1() defined?

[celia05es]

Yes, alertContents1 is defined but it does not even execute it!.
I put an alert just before makeResquest(1,url) and it does not even fire!!

[digital-ether]

So the error happens in function alertContents()

Try putting some alerts in there to see just how far you go.

I believe, if you put:

window.onerror = function(err, url, line) { alert(err+' '+line+' '+url); };

anywhere in your js. Your should get the alert with the error msg and line numbers for uncaught exceptions.

Here is a bit on debugging in IE:
http://blogs.msdn.com/ie/archive/2004/10/26/247912.aspx