WebFileUploader + button?

What does the + button on the WebFileUploader control do?
I’d like to get rid of the necessity to have this whole control on my web app, and just do what the plus button does… i.e. open up the client side file select dialog. (As I really don’t need a list of files… Just 1.)

The + button opens the file select dialog to add a file to the uploader control. You can size the control so just the + button is visible and then handle the actual upload in code so as soon as a file is added it is uploaded. This control would be a lot more user friendly if the icon could be changed.

A simple solution would be to have a method that triggers the “+” event. So that instead of having a customer click the “+” you can have the code trigger the event.

Originally, the uploader was an invisible control, where you would hook up your own UI. Unfortunately, it is impossible to show the select dialog in code. The JavaScript method available must be called in the same event loop iteration as the mouse down. But since WE processes logic server-side asynchronously, there is no way to get the response back in the same loop iteration.

So the current control was designed. There is actually a file select object at 0% opacity hiding on the + button. It’s a terrible hack, but options are extremely limited.

Still a terrible hack, but the following would solve my problem (and that of a few others)
Add a property that changes the file select object to the size of the whole control. Then you can style the complete control as 0% opacity and overlay it to a custom button.