Post URL Variables through FileUploader

I’m working on a file uploader that needs to pass a few variables to the php that will post. I’ve seen how the var posts work if it’s a form, but this one’s a little tricky. Here’s the uplaod fiunction I’m got so far:

var allTypes:Array = new Array();

var fileRef:FileReference = new FileReference();

upload.onRelease = function()

How could i make the “ID” section the URL variable? Any help would be absolutely amazing!