[Javascript] How Do I Upload a File in One Window And Submit the Form In The Other Window?

[Dan Anderson]

I have a web page where I want the user to click a button to see a pop
up window where they can browse files on their computer to upload and
then when they click the submit button have the popup close and the form
to be submitted to the main window.

How would I go about doing this?

Thanks in advance,

Dan