simple XMLHttpRequest logging function

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Steviebone

I am using XMLHttpRequest as a simple one way ajax logging function. No server response is needed. The request does not cross domains.

This code works as expected:

var client2 = new XMLHttpRequest();
client2.open("GET", "program?url=c",true);
client2.send();
alert('sent');
return true;

however, as soon as I remove the alert()

var client2 = new XMLHttpRequest();
client2.open("GET", "program?url=c",true);
client2.send();
return true;

the server never receives the call...

When I step thru this in firebug, I can remove the alert line and once I step thru to the return line the function works as expected. But as soon as I eliminate the debugger (no break) it ceases to work again? very strange. no errors thrown.

what am I missing here?

This is a one way communication to a log file on the server (same domain), no response is needed.

Thanks in advance for any advice... I'm sure I'm just being dense...

Steviebone

update: this function seems to work in IE but not firefox... in firefox the behavior is inconsistent... is there anything about XMLHttpRequest that is browser specific?

Steviebone

update 2: I have tested this on crossbrower testing site live and determined that it is not a problem localized to my machine. The code works as expected in IE but requires the alert() to be fired in Firefox. Very strange. Any suggestions on a work around? Pleeeeeeze?

Steviebone

update again... I tried this code with jquery.ajax with same results... in firefox, the request only works if the alert() is present. I removed firebug, no luck. Tried corssbrowser testing again, same results.

Steviebone

fascinating... in every debugger using step breakpoints the function works as expected until the breakpoints are removed, then the problem returns..

even more fascinating... setting the async to false also fixes the problem... but I don't want a synchronous event... so what could the culprit be?

Steviebone

I know I'm talking to myself but in case someone else stumbles across this some day...

Changing the async flag to false solves the problem apparently. (There were some random issues so I can't say that 100% definitvely yet).

It is confusing to me that the code runs fine in IE. Since it is a simple message to the server I dont' see how timing (sync/async) should matter. Note that it is not the response timing that is an issue because the server never receives the request (and so therefore no reply). The logs to the server are busy but I have done several tests that indicate that the request is never received at all in these instances.

As near as I can tell, the send() fails for some reason with no exception or error thrown that I can find.

Adding IE code is probably a good idea. I left it out for now because the problem is w/ Firefox, and not IE. The code runs fine in IE. I did experiment with adding a readystatechange hook even tho a reply is not needed but saw no difference. I may experiment with this a bit more.

If the problem persists I will try and craft a separate page for testing that I am able to share.

tenfold

I've been reading your thread, I just don't know much about xhr or how to solve your problem.

Can you post the full code you're testing? I see 'return true' but not inside a function, which should indicate either an error or that you posted incomplete code.