New in version 3.2.
Styled Inputs that allow a user to choose or upload files.
FileUploadInput(form, bound_field, ignore_concurrency_change=False)¶
Controls are provided so you can cancel uploads that are in progress or remove ones that have finished. While a file is uploading a progress bar is also shown.
Changed in version 5.0: Added ignore_concurrency_change
Yields one or more strings representing the database value of this Widget.
This is used to determine whether or not the database has changed since a page was rendered, because if it did, the page is considered out of date and needs to be refreshed.
By default only
Inputparticipate in this algorithm, but you may override this method for your
Widgetsubclass to make it participate as well - presuming it can somehow be related to a value in the database.
New in version 5.0.