iframe reload issue firefox file upload

My ascx does support postback(dont ask why), I do an ajax call to save all the data on page, but I have to do a file upload as well so I am using an iframe for it. Everything works well expect for in the firefox.

In the firefox it all works well for the first time not the 2nd time. i.e. if the form filled and files uploaded and submitted for the first time it works but if I do the sa开发者_C百科me thing for the 2nd time (without refreshing the web page) it doesnt.

I did try reloading the iframe from the javascript but that doesnt seem to solve the issue. Any thoughts?

May be this is related to the cache.
Try to add a parameter to the url of your iframe like:

var ifr = document.getElementById('theIframe');
ifr.src = '/pathToFile/file.html?nocache=' + new Date().getTime();