Where are you saving them?
With a submit to SharePoint or a file share you can create the name with a
function.
Typiclaly a concat(year, "-",IDNum) or something like that for your example.
The key is how you keep track of the next number in your sequence.
You have to have some external record that saves what has been used so that
the next can be calculated. This gets very complex if you have many
simultaneous users.
I would suggest using some other data from your form that will make them
unique rather than sequential numbering. now() typically will not duplicate.
You would need an XML list or a SharePoint list or a database to keep track
of the next ID or to query the saved files and get the mawimum. You would
want to do this right before save so that other forms are not grabbing the
same number at the same time so you want the check, calculation, and update
the list as quickly as possible to prevent duplication.
I use web services and SQL primarily so each form is given a sequential ID
by SQL when it is saved so there are no duplicates, which is another option.
