如果没有点击提交按钮，如何将文件上传到临时目录并删除文件？

I have a form that I want to use uploadify on. I have set the uploadify to upload the files on auto when the file is selected. I want to do something like, upload the file to a temporary directory such that the filename of the file is saved in the hidden file, and when the user clicks submit, the file is moved to the upload directory. but if the user exits the page or don't click submit, the temporary file should be deleted on the fly. I am new to uploadify. Seeking some help. I have a form that I want to use uploadify on.