Stopping process after close browser

I have a asp.net 2.0 page c# running a process that does multiple uploads to an ftp server through a FileManager.cs class. The problem is, if the browser closes, the process keep going and keeps uploading. Is there an easy way to detect the browser closing in asp.net?

I have looked around and all things point to the body tag, adding onunload="javascriptFunction" .... but i don't want to do this in javascript, I need it to work in the c# code behind.

It would be nice if i could also avoid ajax

 thanks,

- Roman
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